diff --git a/src/Makefile.am b/src/Makefile.am
index 45bccbcc5..dfd7bb85b 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -106,6 +106,7 @@ BITCOIN_CORE_H = \
   consensus/validation.h \
   core_io.h \
   darksend.h \
+  dsnotificationinterface.h \
   darksend-relay.h \
   core_memusage.h \
   hash.h \
@@ -249,6 +250,7 @@ libbitcoin_wallet_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libbitcoin_wallet_a_SOURCES = \
   activemasternode.cpp \
   darksend.cpp \
+  dsnotificationinterface.cpp \
   darksend-relay.cpp \
   instantx.cpp \
   masternode.cpp \
diff --git a/src/darksend.cpp b/src/darksend.cpp
index 395c0b8db..eb96db78d 100644
--- a/src/darksend.cpp
+++ b/src/darksend.cpp
@@ -450,7 +450,7 @@ std::string CDarksendPool::GetStatus()
     showingDarkSendMessage += 10;
     std::string suffix = "";
 
-    if(chainActive.Tip()->nHeight - cachedLastSuccess < minBlockSpacing || !masternodeSync.IsBlockchainSynced()) {
+    if((pCurrentBlockIndex && pCurrentBlockIndex->nHeight - cachedLastSuccess < minBlockSpacing) || !masternodeSync.IsBlockchainSynced()) {
         return strAutoDenomResult;
     }
     switch(state) {
@@ -570,10 +570,10 @@ void CDarksendPool::CheckFinalTransaction()
 
     CWalletTx txNew = CWalletTx(pwalletMain, finalTransaction);
 
-    LOCK2(cs_main, pwalletMain->cs_wallet);
-    {
-        LogPrint("darksend", "Transaction 2: %s\n", txNew.ToString());
+    LogPrint("darksend", "Transaction 2: %s\n", txNew.ToString());
 
+    {
+        LOCK(cs_main);
         // See if the transaction is valid
         if (!txNew.AcceptToMemoryPool(false, true))
         {
@@ -585,58 +585,57 @@ void CDarksendPool::CheckFinalTransaction()
             RelayCompletedTransaction(sessionID, true, ERR_INVALID_TX);
             return;
         }
-
-        LogPrintf("CDarksendPool::Check() -- IS MASTER -- TRANSMITTING DARKSEND\n");
-
-        // sign a message
-
-        int64_t sigTime = GetAdjustedTime();
-        std::string strMessage = txNew.GetHash().ToString() + boost::lexical_cast<std::string>(sigTime);
-        std::string strError = "";
-        std::vector<unsigned char> vchSig;
-        CKey key2;
-        CPubKey pubkey2;
-
-        if(!darkSendSigner.SetKey(strMasterNodePrivKey, strError, key2, pubkey2))
-        {
-            LogPrintf("CDarksendPool::Check() - ERROR: Invalid Masternodeprivkey: '%s'\n", strError);
-            return;
-        }
-
-        if(!darkSendSigner.SignMessage(strMessage, strError, vchSig, key2)) {
-            LogPrintf("CDarksendPool::Check() - Sign message failed\n");
-            return;
-        }
-
-        if(!darkSendSigner.VerifyMessage(pubkey2, vchSig, strMessage, strError)) {
-            LogPrintf("CDarksendPool::Check() - Verify message failed\n");
-            return;
-        }
-
-        if(!mapDarksendBroadcastTxes.count(txNew.GetHash())){
-            CDarksendBroadcastTx dstx;
-            dstx.tx = txNew;
-            dstx.vin = activeMasternode.vin;
-            dstx.vchSig = vchSig;
-            dstx.sigTime = sigTime;
-
-            mapDarksendBroadcastTxes.insert(make_pair(txNew.GetHash(), dstx));
-        }
-
-        CInv inv(MSG_DSTX, txNew.GetHash());
-        RelayInv(inv);
-
-        // Tell the clients it was successful
-        RelayCompletedTransaction(sessionID, false, MSG_SUCCESS);
-
-        // Randomly charge clients
-        ChargeRandomFees();
-
-        // Reset
-        LogPrint("darksend", "CDarksendPool::Check() -- COMPLETED -- RESETTING\n");
-        SetNull();
-        RelayStatus(sessionID, GetState(), GetEntriesCount(), MASTERNODE_RESET);
     }
+    LogPrintf("CDarksendPool::Check() -- IS MASTER -- TRANSMITTING DARKSEND\n");
+
+    // sign a message
+
+    int64_t sigTime = GetAdjustedTime();
+    std::string strMessage = txNew.GetHash().ToString() + boost::lexical_cast<std::string>(sigTime);
+    std::string strError = "";
+    std::vector<unsigned char> vchSig;
+    CKey key2;
+    CPubKey pubkey2;
+
+    if(!darkSendSigner.SetKey(strMasterNodePrivKey, strError, key2, pubkey2))
+    {
+        LogPrintf("CDarksendPool::Check() - ERROR: Invalid Masternodeprivkey: '%s'\n", strError);
+        return;
+    }
+
+    if(!darkSendSigner.SignMessage(strMessage, strError, vchSig, key2)) {
+        LogPrintf("CDarksendPool::Check() - Sign message failed\n");
+        return;
+    }
+
+    if(!darkSendSigner.VerifyMessage(pubkey2, vchSig, strMessage, strError)) {
+        LogPrintf("CDarksendPool::Check() - Verify message failed\n");
+        return;
+    }
+
+    if(!mapDarksendBroadcastTxes.count(txNew.GetHash())){
+        CDarksendBroadcastTx dstx;
+        dstx.tx = txNew;
+        dstx.vin = activeMasternode.vin;
+        dstx.vchSig = vchSig;
+        dstx.sigTime = sigTime;
+
+        mapDarksendBroadcastTxes.insert(make_pair(txNew.GetHash(), dstx));
+    }
+
+    CInv inv(MSG_DSTX, txNew.GetHash());
+    RelayInv(inv);
+
+    // Tell the clients it was successful
+    RelayCompletedTransaction(sessionID, false, MSG_SUCCESS);
+
+    // Randomly charge clients
+    ChargeRandomFees();
+
+    // Reset
+    LogPrint("darksend", "CDarksendPool::Check() -- COMPLETED -- RESETTING\n");
+    SetNull();
+    RelayStatus(sessionID, GetState(), GetEntriesCount(), MASTERNODE_RESET);
 }
 
 //
@@ -1342,7 +1341,7 @@ void CDarksendPool::CompletedTransaction(bool error, int errorID)
         SetNull();
 
         // To avoid race conditions, we'll only let DS run once per block
-        cachedLastSuccess = chainActive.Tip()->nHeight;
+        cachedLastSuccess = pCurrentBlockIndex->nHeight;
     }
     lastMessage = GetMessageByID(errorID);
 }
@@ -1361,6 +1360,9 @@ bool CDarksendPool::DoAutomaticDenominating(bool fDryRun)
 {
     if(!fEnableDarksend) return false;
     if(fMasterNode) return false;
+
+    if(!pCurrentBlockIndex) return false;
+
     if(state == POOL_STATUS_ERROR || state == POOL_STATUS_SUCCESS) return false;
     if(GetEntriesCount() > 0) {
         strAutoDenomResult = _("Mixing in progress...");
@@ -1383,7 +1385,7 @@ bool CDarksendPool::DoAutomaticDenominating(bool fDryRun)
         return false;
     }
 
-    if(!fDarksendMultiSession && chainActive.Tip()->nHeight - cachedLastSuccess < minBlockSpacing) {
+    if(!fDarksendMultiSession && pCurrentBlockIndex->nHeight - cachedLastSuccess < minBlockSpacing) {
         LogPrintf("CDarksendPool::DoAutomaticDenominating - Last successful Darksend action was too recent\n");
         strAutoDenomResult = _("Last successful Darksend action was too recent.");
         return false;
@@ -1704,7 +1706,7 @@ bool CDarksendPool::MakeCollateralAmounts()
         return false;
     }
 
-    cachedLastSuccess = chainActive.Tip()->nHeight;
+    cachedLastSuccess = pCurrentBlockIndex->nHeight;
 
     return true;
 }
@@ -1795,7 +1797,7 @@ bool CDarksendPool::CreateDenominated(CAmount nTotalValue)
 
     // use the same cachedLastSuccess as for DS mixinx to prevent race
     if(pwalletMain->CommitTransaction(wtx, reservekeyChange))
-        cachedLastSuccess = chainActive.Tip()->nHeight;
+        cachedLastSuccess = pCurrentBlockIndex->nHeight;
     else
         LogPrintf("CreateDenominated: CommitTransaction failed!\n");
 
@@ -2198,6 +2200,15 @@ void CDarksendPool::RelayCompletedTransaction(const int sessionID, const bool er
         pnode->PushMessage(NetMsgType::DSSTATUSUPDATE, sessionID, error, errorID);
 }
 
+void CDarksendPool::UpdatedBlockTip(const CBlockIndex *pindex)
+{
+    pCurrentBlockIndex = pindex;
+    LogPrint("darksend", "pCurrentBlockIndex->nHeight: %d\n", pCurrentBlockIndex->nHeight);
+
+    if(!fLiteMode && masternodeSync.RequestedMasternodeAssets > MASTERNODE_SYNC_LIST)
+        NewBlock();
+}
+
 //TODO: Rename/move to core
 void ThreadCheckDarkSendPool()
 {
diff --git a/src/darksend.h b/src/darksend.h
index b38d52f42..028e2d413 100644
--- a/src/darksend.h
+++ b/src/darksend.h
@@ -289,6 +289,9 @@ private:
 
     int64_t lastNewBlock;
 
+    // Keep track of current block index
+    const CBlockIndex *pCurrentBlockIndex;
+
     std::vector<CAmount> darkSendDenominationsSkipped;
 
     //debugging data
@@ -535,6 +538,8 @@ public:
     void RelayIn(const std::vector<CTxDSIn>& vin, const CAmount& nAmount, const CTransaction& txCollateral, const std::vector<CTxDSOut>& vout);
     void RelayStatus(const int sessionID, const int newState, const int newEntriesCount, const int newAccepted, const int errorID=MSG_NOERR);
     void RelayCompletedTransaction(const int sessionID, const bool error, const int errorID);
+
+    void UpdatedBlockTip(const CBlockIndex *pindex);
 };
 
 void ThreadCheckDarkSendPool();
diff --git a/src/dsnotificationinterface.cpp b/src/dsnotificationinterface.cpp
new file mode 100644
index 000000000..7fc227feb
--- /dev/null
+++ b/src/dsnotificationinterface.cpp
@@ -0,0 +1,25 @@
+// Copyright (c) 2015 The Dash Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "dsnotificationinterface.h"
+#include "darksend.h"
+#include "masternode-budget.h"
+#include "masternode-payments.h"
+#include "masternode-sync.h"
+
+CDSNotificationInterface::CDSNotificationInterface()
+{
+}
+
+CDSNotificationInterface::~CDSNotificationInterface()
+{
+}
+
+void CDSNotificationInterface::UpdatedBlockTip(const CBlockIndex *pindex)
+{
+    darkSendPool.UpdatedBlockTip(pindex);
+    mnpayments.UpdatedBlockTip(pindex);
+    budget.UpdatedBlockTip(pindex);
+    masternodeSync.UpdatedBlockTip(pindex);
+}
diff --git a/src/dsnotificationinterface.h b/src/dsnotificationinterface.h
new file mode 100644
index 000000000..abc0d501b
--- /dev/null
+++ b/src/dsnotificationinterface.h
@@ -0,0 +1,24 @@
+// Copyright (c) 2015 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_DSNOTIFICATIONINTERFACE_H
+#define BITCOIN_DSNOTIFICATIONINTERFACE_H
+
+#include "validationinterface.h"
+
+class CDSNotificationInterface : public CValidationInterface
+{
+public:
+    // virtual CDSNotificationInterface();
+    CDSNotificationInterface();
+    virtual ~CDSNotificationInterface();
+
+protected:
+    // CValidationInterface
+    void UpdatedBlockTip(const CBlockIndex *pindex);
+
+private:
+};
+
+#endif // BITCOIN_DSNOTIFICATIONINTERFACE_H
diff --git a/src/init.cpp b/src/init.cpp
index 6b8ea4c9b..f5225746e 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -70,6 +70,8 @@
 #include "zmq/zmqnotificationinterface.h"
 #endif
 
+#include "dsnotificationinterface.h"
+
 using namespace std;
 
 #ifdef ENABLE_WALLET
@@ -87,6 +89,8 @@ static const bool DEFAULT_STOPAFTERBLOCKIMPORT = false;
 static CZMQNotificationInterface* pzmqNotificationInterface = NULL;
 #endif
 
+static CDSNotificationInterface* pdsNotificationInterface = NULL;
+
 #ifdef WIN32
 // Win32 LevelDB doesn't use filedescriptors, and the ones used for
 // accessing block files don't count towards the fd_set size limit
@@ -254,6 +258,12 @@ void PrepareShutdown()
     }
 #endif
 
+    if (pdsNotificationInterface) {
+        UnregisterValidationInterface(pdsNotificationInterface);
+        delete pdsNotificationInterface;
+        pdsNotificationInterface = NULL;
+    }
+
 #ifndef WIN32
     try {
         boost::filesystem::remove(GetPidFile());
@@ -1428,6 +1438,10 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
         RegisterValidationInterface(pzmqNotificationInterface);
     }
 #endif
+
+    pdsNotificationInterface = new CDSNotificationInterface();
+    RegisterValidationInterface(pdsNotificationInterface);
+
     if (mapArgs.count("-maxuploadtarget")) {
         CNode::SetMaxOutboundTarget(GetArg("-maxuploadtarget", DEFAULT_MAX_UPLOAD_TARGET)*1024*1024);
     }
@@ -1938,6 +1952,10 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
     darkSendPool.InitDenominations();
     darkSendPool.InitCollateralAddress();
 
+    // force UpdatedBlockTip to initialize pCurrentBlockIndex for DS, MN payments and budgets
+    GetMainSignals().UpdatedBlockTip(chainActive.Tip());
+
+    // start dash-darksend thread
     threadGroup.create_thread(boost::bind(&ThreadCheckDarkSendPool));
 
     // ********************************************************* Step 11: start node
diff --git a/src/instantx.cpp b/src/instantx.cpp
index 6e9907dc6..5286cbeb6 100644
--- a/src/instantx.cpp
+++ b/src/instantx.cpp
@@ -235,7 +235,13 @@ int64_t CreateNewLock(CTransaction tx)
         This prevents attackers from using transaction mallibility to predict which masternodes
         they'll use.
     */
-    int nBlockHeight = (chainActive.Tip()->nHeight - nTxAge)+4;
+    int nBlockHeight = 0;
+    {
+        LOCK(cs_main);
+        CBlockIndex* tip = chainActive.Tip();
+        if(tip) nBlockHeight = tip->nHeight - nTxAge + 4;
+        else return 0;
+    }
 
     if (!mapTxLocks.count(tx.GetHash())){
         LogPrintf("CreateNewLock - New Transaction Lock %s !\n", tx.GetHash().ToString().c_str());
@@ -434,8 +440,6 @@ int64_t GetAverageVoteTime()
 
 void CleanTransactionLocksList()
 {
-    if(chainActive.Tip() == NULL) return;
-
     std::map<uint256, CTransactionLock>::iterator it = mapTxLocks.begin();
 
     while(it != mapTxLocks.end()) {
@@ -460,7 +464,6 @@ void CleanTransactionLocksList()
             it++;
         }
     }
-
 }
 
 uint256 CConsensusVote::GetHash() const
diff --git a/src/main.cpp b/src/main.cpp
index 42089ec7e..1755860dd 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3527,14 +3527,6 @@ bool ProcessNewBlock(CValidationState& state, const CChainParams& chainparams, c
     if (!ActivateBestChain(state, chainparams, pblock))
         return error("%s: ActivateBestChain failed", __func__);
 
-    if(!fLiteMode){
-        if (masternodeSync.RequestedMasternodeAssets > MASTERNODE_SYNC_LIST) {
-            darkSendPool.NewBlock();
-            mnpayments.ProcessBlock(GetHeight()+10);
-            budget.NewBlock();
-        }
-    }
-
     LogPrintf("%s : ACCEPTED\n", __func__);
     return true;
 }
diff --git a/src/masternode-budget.cpp b/src/masternode-budget.cpp
index 7c7cf15c9..aaa86df85 100644
--- a/src/masternode-budget.cpp
+++ b/src/masternode-budget.cpp
@@ -57,6 +57,7 @@ bool IsBudgetCollateralValid(uint256 nTxCollateralHash, uint256 nExpectedHash, s
         return false;
     }
 
+    LOCK(cs_main);
     int conf = GetIXConfirmations(nTxCollateralHash);
     if (nBlockHash != uint256()) {
         BlockMap::iterator mi = mapBlockIndex.find(nBlockHash);
@@ -109,12 +110,11 @@ void CBudgetManager::CheckOrphanVotes()
 
 void CBudgetManager::SubmitFinalBudget()
 {
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(!pindexPrev) return;
+    if(!pCurrentBlockIndex) return;
 
-    int nBlockStart = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+    int nBlockStart = pCurrentBlockIndex->nHeight - pCurrentBlockIndex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
     if(nSubmittedFinalBudget >= nBlockStart) return;
-    if(nBlockStart - pindexPrev->nHeight > 576*2) return; //submit final budget 2 days before payment
+    if(nBlockStart - pCurrentBlockIndex->nHeight > 576*2) return; //submit final budget 2 days before payment
 
     std::vector<CBudgetProposal*> vBudgetProposals = budget.GetBudget();
     std::string strBudgetName = "main";
@@ -136,7 +136,7 @@ void CBudgetManager::SubmitFinalBudget()
     CFinalizedBudgetBroadcast tempBudget(strBudgetName, nBlockStart, vecTxBudgetPayments, uint256());
     if(mapSeenFinalizedBudgets.count(tempBudget.GetHash())) {
         LogPrintf("CBudgetManager::SubmitFinalBudget - Budget already exists - %s\n", tempBudget.GetHash().ToString());    
-        nSubmittedFinalBudget = pindexPrev->nHeight;
+        nSubmittedFinalBudget = pCurrentBlockIndex->nHeight;
         return; //already exists
     }
 
@@ -177,7 +177,7 @@ void CBudgetManager::SubmitFinalBudget()
     CFinalizedBudgetBroadcast finalizedBudgetBroadcast(strBudgetName, nBlockStart, vecTxBudgetPayments, tx.GetHash());
 
     std::string strError = "";
-    if(!finalizedBudgetBroadcast.IsValid(strError)){
+    if(!finalizedBudgetBroadcast.IsValid(pCurrentBlockIndex, strError)){
         LogPrintf("CBudgetManager::SubmitFinalBudget - Invalid finalized budget - %s \n", strError);
         return;
     }
@@ -355,7 +355,7 @@ void DumpBudgets()
 bool CBudgetManager::AddFinalizedBudget(CFinalizedBudget& finalizedBudget)
 {
     std::string strError = "";
-    if(!finalizedBudget.IsValid(strError)) return false;
+    if(!finalizedBudget.IsValid(pCurrentBlockIndex, strError)) return false;
 
     if(mapFinalizedBudgets.count(finalizedBudget.GetHash())) {
         return false;
@@ -369,7 +369,7 @@ bool CBudgetManager::AddProposal(CBudgetProposal& budgetProposal)
 {
     LOCK(cs);
     std::string strError = "";
-    if(!budgetProposal.IsValid(strError)) {
+    if(!budgetProposal.IsValid(pCurrentBlockIndex, strError)) {
         LogPrintf("CBudgetManager::AddProposal - invalid budget proposal - %s\n", strError);
         return false;
     }
@@ -386,9 +386,7 @@ void CBudgetManager::CheckAndRemove()
 {
     LogPrintf("CBudgetManager::CheckAndRemove \n");
 
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(!pindexPrev) return;
-
+    if(!pCurrentBlockIndex) return;
 
     std::string strError = "";
     std::map<uint256, CFinalizedBudget>::iterator it = mapFinalizedBudgets.begin();
@@ -396,13 +394,13 @@ void CBudgetManager::CheckAndRemove()
     {
         CFinalizedBudget* pfinalizedBudget = &((*it).second);
 
-        pfinalizedBudget->fValid = pfinalizedBudget->IsValid(strError);
+        pfinalizedBudget->fValid = pfinalizedBudget->IsValid(pCurrentBlockIndex, strError);
         if(pfinalizedBudget->fValid) {
             pfinalizedBudget->AutoCheck();
             ++it;
         
         // if it's too old, remove it
-        } else if(pfinalizedBudget->nBlockStart != 0 && pfinalizedBudget->nBlockStart < pindexPrev->nHeight - Params().GetConsensus().nBudgetPaymentsCycleBlocks) {
+        } else if(pfinalizedBudget->nBlockStart != 0 && pfinalizedBudget->nBlockStart < pCurrentBlockIndex->nHeight - Params().GetConsensus().nBudgetPaymentsCycleBlocks) {
             mapFinalizedBudgets.erase(it++);
             LogPrintf("CBudgetManager::CheckAndRemove - removing budget %s\n", pfinalizedBudget->GetHash().ToString());
         }
@@ -412,7 +410,7 @@ void CBudgetManager::CheckAndRemove()
     while(it2 != mapProposals.end())
     {
         CBudgetProposal* pbudgetProposal = &((*it2).second);
-        pbudgetProposal->fValid = pbudgetProposal->IsValid(strError);
+        pbudgetProposal->fValid = pbudgetProposal->IsValid(pCurrentBlockIndex, strError);
         ++it2;
     }
 }
@@ -421,8 +419,7 @@ void CBudgetManager::FillBlockPayee(CMutableTransaction& txNew, CAmount nFees)
 {
     LOCK(cs);
 
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(!pindexPrev) return;
+    if(!pCurrentBlockIndex) return;
 
     int nHighestCount = 0;
     CScript payee;
@@ -435,19 +432,17 @@ void CBudgetManager::FillBlockPayee(CMutableTransaction& txNew, CAmount nFees)
     {
         CFinalizedBudget* pfinalizedBudget = &((*it).second);
         if(pfinalizedBudget->GetVoteCount() > nHighestCount &&
-                pindexPrev->nHeight + 1 >= pfinalizedBudget->GetBlockStart() &&
-                pindexPrev->nHeight + 1 <= pfinalizedBudget->GetBlockEnd() &&
-                pfinalizedBudget->GetPayeeAndAmount(pindexPrev->nHeight + 1, payee, nAmount)){
+                pCurrentBlockIndex->nHeight + 1 >= pfinalizedBudget->GetBlockStart() &&
+                pCurrentBlockIndex->nHeight + 1 <= pfinalizedBudget->GetBlockEnd() &&
+                pfinalizedBudget->GetPayeeAndAmount(pCurrentBlockIndex->nHeight + 1, payee, nAmount)){
                     nHighestCount = pfinalizedBudget->GetVoteCount();
         }
 
         ++it;
     }
 
-    CAmount blockValue = nFees + GetBlockSubsidy(pindexPrev->nBits, pindexPrev->nHeight, Params().GetConsensus());
-
     //miners get the full amount on these blocks
-    txNew.vout[0].nValue = blockValue;
+    txNew.vout[0].nValue = nFees + GetBlockSubsidy(pCurrentBlockIndex->nBits, pCurrentBlockIndex->nHeight, Params().GetConsensus());
 
     if(nHighestCount > 0){
         txNew.vout.resize(2);
@@ -531,13 +526,12 @@ bool CBudgetManager::IsBudgetPaymentBlock(int nBlockHeight)
 
 bool CBudgetManager::HasNextFinalizedBudget()
 {
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(!pindexPrev) return false;
+    if(!pCurrentBlockIndex) return false;
 
     if(masternodeSync.IsBudgetFinEmpty()) return true;
 
-    int nBlockStart = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
-    if(nBlockStart - pindexPrev->nHeight > 576*2) return true; //we wouldn't have the budget yet
+    int nBlockStart = pCurrentBlockIndex->nHeight - pCurrentBlockIndex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+    if(nBlockStart - pCurrentBlockIndex->nHeight > 576*2) return true; //we wouldn't have the budget yet
 
     if(budget.IsBudgetPaymentBlock(nBlockStart)) return true;
 
@@ -649,10 +643,9 @@ std::vector<CBudgetProposal*> CBudgetManager::GetBudget()
     std::vector<CBudgetProposal*> vBudgetProposalsRet;
 
     CAmount nBudgetAllocated = 0;
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(pindexPrev == NULL) return vBudgetProposalsRet;
+    if(!pCurrentBlockIndex) return vBudgetProposalsRet;
 
-    int nBlockStart = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+    int nBlockStart = pCurrentBlockIndex->nHeight - pCurrentBlockIndex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
     int nBlockEnd  =  nBlockStart + Params().GetConsensus().nBudgetPaymentsWindowBlocks;
     CAmount nTotalBudget = GetTotalBudget(nBlockStart);
 
@@ -765,7 +758,7 @@ std::string CBudgetManager::GetRequiredPaymentsString(int nBlockHeight)
 
 CAmount CBudgetManager::GetTotalBudget(int nHeight)
 {
-    if(chainActive.Tip() == NULL) return 0;
+    if(!pCurrentBlockIndex) return 0;
 
     //get min block value and calculate from that
     CAmount nSubsidy = 5 * COIN;
@@ -793,6 +786,8 @@ void CBudgetManager::NewBlock()
     TRY_LOCK(cs, fBudgetNewBlock);
     if(!fBudgetNewBlock) return;
 
+    if(!pCurrentBlockIndex) return;
+
     if (masternodeSync.RequestedMasternodeAssets <= MASTERNODE_SYNC_BUDGET) return;
 
     if (strBudgetMode == "suggest") { //suggest the budget we see
@@ -800,12 +795,12 @@ void CBudgetManager::NewBlock()
     }
 
     //this function should be called 1/6 blocks, allowing up to 100 votes per day on all proposals
-    if(chainActive.Height() % 6 != 0) return;
+    if(pCurrentBlockIndex->nHeight % 6 != 0) return;
 
     // incremental sync with our peers
     if(masternodeSync.IsSynced()){
         LogPrintf("CBudgetManager::NewBlock - incremental sync started\n");
-        if(chainActive.Height() % 600 == rand() % 600) {
+        if(pCurrentBlockIndex->nHeight % 600 == rand() % 600) {
             ClearSeen();
             ResetSync();
         }
@@ -814,10 +809,9 @@ void CBudgetManager::NewBlock()
         BOOST_FOREACH(CNode* pnode, vNodes)
             if(pnode->nVersion >= MIN_BUDGET_PEER_PROTO_VERSION) 
                 Sync(pnode, uint256(), true);
-        
+
         MarkSynced();
     }
-     
 
     CheckAndRemove();
 
@@ -854,7 +848,7 @@ void CBudgetManager::NewBlock()
             continue;
         }
 
-        if(!(*it4).IsValid(strError)) {
+        if(!(*it4).IsValid(pCurrentBlockIndex, strError)) {
             LogPrintf("mprop (immature) - invalid budget proposal - %s\n", strError);
             it4 = vecImmatureBudgetProposals.erase(it4); 
             continue;
@@ -877,7 +871,7 @@ void CBudgetManager::NewBlock()
             continue;
         }
 
-        if(!(*it5).IsValid(strError)) {
+        if(!(*it5).IsValid(pCurrentBlockIndex, strError)) {
             LogPrintf("fbs (immature) - invalid finalized budget - %s\n", strError);
             it5 = vecImmatureFinalizedBudgets.erase(it5); 
             continue;
@@ -939,7 +933,7 @@ void CBudgetManager::ProcessMessage(CNode* pfrom, std::string& strCommand, CData
 
         mapSeenMasternodeBudgetProposals.insert(make_pair(budgetProposalBroadcast.GetHash(), budgetProposalBroadcast));
 
-        if(!budgetProposalBroadcast.IsValid(strError)) {
+        if(!budgetProposalBroadcast.IsValid(pCurrentBlockIndex, strError)) {
             LogPrintf("mprop - invalid budget proposal - %s\n", strError);
             return;
         }
@@ -980,7 +974,7 @@ void CBudgetManager::ProcessMessage(CNode* pfrom, std::string& strCommand, CData
             mnodeman.AskForMN(pfrom, vote.vin);
             return;
         }
-        
+
         std::string strError = "";
         if(UpdateProposal(vote, pfrom, strError)) {
             vote.Relay();
@@ -1010,7 +1004,7 @@ void CBudgetManager::ProcessMessage(CNode* pfrom, std::string& strCommand, CData
 
         mapSeenFinalizedBudgets.insert(make_pair(finalizedBudgetBroadcast.GetHash(), finalizedBudgetBroadcast));
 
-        if(!finalizedBudgetBroadcast.IsValid(strError)) {
+        if(!finalizedBudgetBroadcast.IsValid(pCurrentBlockIndex, strError)) {
             LogPrintf("fbs - invalid finalized budget - %s\n", strError);
             return;
         }
@@ -1320,7 +1314,7 @@ CBudgetProposal::CBudgetProposal(std::string strProposalNameIn, std::string strU
     nFeeTXHash = nFeeTXHashIn;
 }
 
-bool CBudgetProposal::IsValid(std::string& strError, bool fCheckCollateral)
+bool CBudgetProposal::IsValid(const CBlockIndex* pindex, std::string& strError, bool fCheckCollateral)
 {
     if(GetNoCount() - GetYesCount() > mnodeman.CountEnabled(MIN_BUDGET_PEER_PROTO_VERSION)/10){
          strError = "Active removal";
@@ -1332,11 +1326,13 @@ bool CBudgetProposal::IsValid(std::string& strError, bool fCheckCollateral)
         return false;
     }
 
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(pindexPrev == NULL) {strError = "Tip is NULL"; return true;}
+    if(!pindex) {
+        strError = "Tip is NULL";
+        return true;
+    }
 
     if(nBlockStart % Params().GetConsensus().nBudgetPaymentsCycleBlocks != 0){
-        int nNext = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+        int nNext = pindex->nHeight - pindex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
         strError = strprintf("Invalid block start - must be a budget cycle block. Next valid block: %d", nNext);
         return false;
     }
@@ -1408,7 +1404,7 @@ bool CBudgetProposal::IsValid(std::string& strError, bool fCheckCollateral)
         return false;
     }
 
-    if(GetBlockEnd() + Params().GetConsensus().nBudgetPaymentsWindowBlocks < pindexPrev->nHeight) return false;
+    if(GetBlockEnd() + Params().GetConsensus().nBudgetPaymentsWindowBlocks < pindex->nHeight) return false;
 
 
     return true;
@@ -1528,14 +1524,13 @@ int CBudgetProposal::GetBlockStartCycle()
     return nBlockStart - nBlockStart % Params().GetConsensus().nBudgetPaymentsCycleBlocks;
 }
 
-int CBudgetProposal::GetBlockCurrentCycle()
+int CBudgetProposal::GetBlockCurrentCycle(const CBlockIndex* pindex)
 {
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(pindexPrev == NULL) return -1;
+    if(!pindex) return -1;
 
-    if(pindexPrev->nHeight >= GetBlockEndCycle()) return -1;
+    if(pindex->nHeight >= GetBlockEndCycle()) return -1;
 
-    return pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+    return pindex->nHeight - pindex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks;
 }
 
 int CBudgetProposal::GetBlockEndCycle()
@@ -1850,7 +1845,7 @@ std::string CFinalizedBudget::GetStatus()
     return retBadHashes + retBadPayeeOrAmount;
 }
 
-bool CFinalizedBudget::IsValid(std::string& strError, bool fCheckCollateral)
+bool CFinalizedBudget::IsValid(const CBlockIndex* pindex, std::string& strError, bool fCheckCollateral)
 {
     //must be the correct block for payment to happen (once a month)
     if(nBlockStart % Params().GetConsensus().nBudgetPaymentsCycleBlocks != 0) {strError = "Invalid BlockStart"; return false;}
@@ -1867,16 +1862,19 @@ bool CFinalizedBudget::IsValid(std::string& strError, bool fCheckCollateral)
     if(fCheckCollateral){
         int nConf = 0;
         if(!IsBudgetCollateralValid(nFeeTXHash, GetHash(), strError2, nTime, nConf)){
-            {strError = "Invalid Collateral : " + strError2; return false;}
+            strError = "Invalid Collateral : " + strError2;
+            return false;
         }
     }
 
     //TODO: if N cycles old, invalid, invalid
 
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(pindexPrev == NULL) return true;
+    if(!pindex) return true;
 
-    if(nBlockStart < pindexPrev->nHeight - Params().GetConsensus().nBudgetPaymentsWindowBlocks) {strError = "Older than current blockHeight"; return false;}
+    if(nBlockStart < pindex->nHeight - Params().GetConsensus().nBudgetPaymentsWindowBlocks) {
+        strError = "Older than current blockHeight";
+        return false;
+    }
 
     return true;
 }
@@ -2059,4 +2057,11 @@ std::string CBudgetManager::ToString() const
     return info.str();
 }
 
+void CBudgetManager::UpdatedBlockTip(const CBlockIndex *pindex)
+{
+    pCurrentBlockIndex = pindex;
+    LogPrint("mnbudget", "pCurrentBlockIndex->nHeight: %d\n", pCurrentBlockIndex->nHeight);
 
+    if(!fLiteMode && masternodeSync.RequestedMasternodeAssets > MASTERNODE_SYNC_LIST)
+        NewBlock();
+}
diff --git a/src/masternode-budget.h b/src/masternode-budget.h
index eb2e1bcc1..1a6b4334b 100644
--- a/src/masternode-budget.h
+++ b/src/masternode-budget.h
@@ -78,6 +78,8 @@ private:
 
     //hold txes until they mature enough to use
     map<uint256, CTransaction> mapCollateral;
+    // Keep track of current block index
+    const CBlockIndex *pCurrentBlockIndex;
 
 public:
     // critical section to protect the inner data structures
@@ -179,6 +181,8 @@ public:
         READWRITE(mapProposals);
         READWRITE(mapFinalizedBudgets);
     }
+
+    void UpdatedBlockTip(const CBlockIndex *pindex);
 };
 
 
@@ -235,7 +239,7 @@ public:
     double GetScore();
     bool HasMinimumRequiredSupport();
 
-    bool IsValid(std::string& strError, bool fCheckCollateral=true);
+    bool IsValid(const CBlockIndex* pindex, std::string& strError, bool fCheckCollateral=true);
 
     std::string GetName() {return strBudgetName; }
     std::string GetProposals();
@@ -427,7 +431,7 @@ public:
     bool HasMinimumRequiredSupport();
     std::pair<std::string, std::string> GetVotes();
 
-    bool IsValid(std::string& strError, bool fCheckCollateral=true);
+    bool IsValid(const CBlockIndex* pindex, std::string& strError, bool fCheckCollateral=true);
     bool IsEstablished();
 
     std::string GetName() {return strProposalName; }
@@ -438,7 +442,7 @@ public:
     int GetTotalPaymentCount();
     int GetRemainingPaymentCount();
     int GetBlockStartCycle();
-    int GetBlockCurrentCycle();
+    int GetBlockCurrentCycle(const CBlockIndex* pindex);
     int GetBlockEndCycle();
     double GetRatio();
     int GetAbsoluteYesCount();
diff --git a/src/masternode-payments.cpp b/src/masternode-payments.cpp
index de8c1daa7..fbd63ad99 100644
--- a/src/masternode-payments.cpp
+++ b/src/masternode-payments.cpp
@@ -183,19 +183,21 @@ void DumpMasternodePayments()
 }
 
 bool IsBlockValueValid(const CBlock& block, CAmount nExpectedValue){
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(pindexPrev == NULL) return true;
-
     int nHeight = 0;
-    if(pindexPrev->GetBlockHash() == block.hashPrevBlock)
-    {
-        nHeight = pindexPrev->nHeight+1;
-    } else { //out of order
-        BlockMap::iterator mi = mapBlockIndex.find(block.hashPrevBlock);
-        if (mi != mapBlockIndex.end() && (*mi).second)
-            nHeight = (*mi).second->nHeight+1;
-    }
 
+    {
+        LOCK(cs_main);
+        if(!chainActive.Tip()) return true;
+
+        if(chainActive.Tip()->GetBlockHash() == block.hashPrevBlock)
+        {
+            nHeight = chainActive.Tip()->nHeight+1;
+        } else { //out of order
+            BlockMap::iterator mi = mapBlockIndex.find(block.hashPrevBlock);
+            if (mi != mapBlockIndex.end() && (*mi).second)
+                nHeight = (*mi).second->nHeight+1;
+        }
+    }
     if(nHeight == 0){
         LogPrintf("IsBlockValueValid() : WARNING: Couldn't find previous block");
     }
@@ -269,10 +271,9 @@ bool IsBlockPayeeValid(const CTransaction& txNew, int nBlockHeight)
 
 void FillBlockPayee(CMutableTransaction& txNew, CAmount nFees)
 {
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(!pindexPrev) return;
+    if(!chainActive.Tip()) return;
 
-    if(IsSporkActive(SPORK_13_ENABLE_SUPERBLOCKS) && budget.IsBudgetPaymentBlock(pindexPrev->nHeight+1)){
+    if(IsSporkActive(SPORK_13_ENABLE_SUPERBLOCKS) && budget.IsBudgetPaymentBlock(chainActive.Tip()->nHeight+1)){
         budget.FillBlockPayee(txNew, nFees);
     } else {
         mnpayments.FillBlockPayee(txNew, nFees);
@@ -290,14 +291,13 @@ std::string GetRequiredPaymentsString(int nBlockHeight)
 
 void CMasternodePayments::FillBlockPayee(CMutableTransaction& txNew, CAmount nFees)
 {
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(!pindexPrev) return;
+    if(!pCurrentBlockIndex) return;
 
     bool hasPayment = true;
     CScript payee;
 
     //spork
-    if(!mnpayments.GetBlockPayee(pindexPrev->nHeight+1, payee)){
+    if(!mnpayments.GetBlockPayee(pCurrentBlockIndex->nHeight+1, payee)){
         //no masternode detected
         CMasternode* winningNode = mnodeman.GetCurrentMasterNode();
         if(winningNode){
@@ -308,8 +308,8 @@ void CMasternodePayments::FillBlockPayee(CMutableTransaction& txNew, CAmount nFe
         }
     }
 
-    CAmount blockValue = nFees + GetBlockSubsidy(pindexPrev->nBits, pindexPrev->nHeight, Params().GetConsensus());
-    CAmount masternodePayment = GetMasternodePayment(pindexPrev->nHeight+1, blockValue);
+    CAmount blockValue = nFees + GetBlockSubsidy(pCurrentBlockIndex->nBits, pCurrentBlockIndex->nHeight, Params().GetConsensus());
+    CAmount masternodePayment = GetMasternodePayment(pCurrentBlockIndex->nHeight+1, blockValue);
 
     txNew.vout[0].nValue = blockValue;
 
@@ -367,17 +367,17 @@ void CMasternodePayments::ProcessMessageMasternodePayments(CNode* pfrom, std::st
 
         if(pfrom->nVersion < MIN_MNW_PEER_PROTO_VERSION) return;
 
-        if(chainActive.Tip() == NULL) return;
+        if(!pCurrentBlockIndex) return;
 
         if(mnpayments.mapMasternodePayeeVotes.count(winner.GetHash())){
-            LogPrint("mnpayments", "mnw - Already seen - %s bestHeight %d\n", winner.GetHash().ToString().c_str(), chainActive.Tip()->nHeight);
+            LogPrint("mnpayments", "mnw - Already seen - %s bestHeight %d\n", winner.GetHash().ToString().c_str(), pCurrentBlockIndex->nHeight);
             masternodeSync.AddedMasternodeWinner(winner.GetHash());
             return;
         }
 
-        int nFirstBlock = chainActive.Tip()->nHeight - (mnodeman.CountEnabled()*1.25);
-        if(winner.nBlockHeight < nFirstBlock || winner.nBlockHeight > chainActive.Tip()->nHeight+20){
-            LogPrint("mnpayments", "mnw - winner out of range - FirstBlock %d Height %d bestHeight %d\n", nFirstBlock, winner.nBlockHeight, chainActive.Tip()->nHeight);
+        int nFirstBlock = pCurrentBlockIndex->nHeight - (mnodeman.CountEnabled()*1.25);
+        if(winner.nBlockHeight < nFirstBlock || winner.nBlockHeight > pCurrentBlockIndex->nHeight+20){
+            LogPrint("mnpayments", "mnw - winner out of range - FirstBlock %d Height %d bestHeight %d\n", nFirstBlock, winner.nBlockHeight, pCurrentBlockIndex->nHeight);
             return;
         }
 
@@ -404,7 +404,7 @@ void CMasternodePayments::ProcessMessageMasternodePayments(CNode* pfrom, std::st
         ExtractDestination(winner.payee, address1);
         CBitcoinAddress address2(address1);
 
-        LogPrint("mnpayments", "mnw - winning vote - Addr %s Height %d bestHeight %d - %s\n", address2.ToString().c_str(), winner.nBlockHeight, chainActive.Tip()->nHeight, winner.vinMasternode.prevout.ToStringShort());
+        LogPrint("mnpayments", "mnw - winning vote - Addr %s Height %d bestHeight %d - %s\n", address2.ToString().c_str(), winner.nBlockHeight, pCurrentBlockIndex->nHeight, winner.vinMasternode.prevout.ToStringShort());
 
         if(mnpayments.AddWinningMasternode(winner)){
             winner.Relay();
@@ -450,14 +450,13 @@ bool CMasternodePayments::IsScheduled(CMasternode& mn, int nNotBlockHeight)
 {
     LOCK(cs_mapMasternodeBlocks);
 
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(pindexPrev == NULL) return false;
+    if(!pCurrentBlockIndex) return false;
 
     CScript mnpayee;
     mnpayee = GetScriptForDestination(mn.pubkey.GetID());
 
     CScript payee;
-    for(int64_t h = pindexPrev->nHeight; h <= pindexPrev->nHeight+8; h++){
+    for(int64_t h = pCurrentBlockIndex->nHeight; h <= pCurrentBlockIndex->nHeight + 8; h++){
         if(h == nNotBlockHeight) continue;
         if(mapMasternodeBlocks.count(h)){
             if(mapMasternodeBlocks[h].GetPayee(payee)){
@@ -593,18 +592,18 @@ bool CMasternodePayments::IsTransactionValid(const CTransaction& txNew, int nBlo
 
 void CMasternodePayments::CleanPaymentList()
 {
+    if(!pCurrentBlockIndex) return;
+
     LOCK2(cs_mapMasternodePayeeVotes, cs_mapMasternodeBlocks);
 
-    if(chainActive.Tip() == NULL) return;
-
-    //keep up to five cycles for historical sake
-    int nLimit = std::max(int(mnodeman.size()*1.25), 1000);
+    // keep a bit more for historical sake but at least 4000
+    int nLimit = std::max(int(mnodeman.size()*1.25), 4000);
 
     std::map<uint256, CMasternodePaymentWinner>::iterator it = mapMasternodePayeeVotes.begin();
     while(it != mapMasternodePayeeVotes.end()) {
         CMasternodePaymentWinner winner = (*it).second;
 
-        if(chainActive.Tip()->nHeight - winner.nBlockHeight > nLimit){
+        if(pCurrentBlockIndex->nHeight - winner.nBlockHeight > nLimit){
             LogPrint("mnpayments", "CMasternodePayments::CleanPaymentList - Removing old Masternode payment - block %d\n", winner.nBlockHeight);
             masternodeSync.mapSeenSyncMNW.erase((*it).first);
             mapMasternodePayeeVotes.erase(it++);
@@ -777,7 +776,7 @@ void CMasternodePayments::Sync(CNode* node, int nCountNeeded)
 {
     LOCK(cs_mapMasternodePayeeVotes);
 
-    if(chainActive.Tip() == NULL) return;
+    if(!pCurrentBlockIndex) return;
 
     int nCount = (mnodeman.CountEnabled()*1.25);
     if(nCountNeeded > nCount) nCountNeeded = nCount;
@@ -786,7 +785,7 @@ void CMasternodePayments::Sync(CNode* node, int nCountNeeded)
     std::map<uint256, CMasternodePaymentWinner>::iterator it = mapMasternodePayeeVotes.begin();
     while(it != mapMasternodePayeeVotes.end()) {
         CMasternodePaymentWinner winner = (*it).second;
-        if(winner.nBlockHeight >= chainActive.Tip()->nHeight-nCountNeeded && winner.nBlockHeight <= chainActive.Tip()->nHeight + 20) {
+        if(winner.nBlockHeight >= pCurrentBlockIndex->nHeight - nCountNeeded && winner.nBlockHeight <= pCurrentBlockIndex->nHeight + 20) {
             node->PushInventory(CInv(MSG_MASTERNODE_WINNER, winner.GetHash()));
             nInvCount++;
         }
@@ -842,3 +841,12 @@ int CMasternodePayments::GetNewestBlock()
 
     return nNewestBlock;
 }
+
+void CMasternodePayments::UpdatedBlockTip(const CBlockIndex *pindex)
+{
+    pCurrentBlockIndex = pindex;
+    LogPrint("mnpayments", "pCurrentBlockIndex->nHeight: %d\n", pCurrentBlockIndex->nHeight);
+
+    if(!fLiteMode && masternodeSync.RequestedMasternodeAssets > MASTERNODE_SYNC_LIST)
+        ProcessBlock(pindex->nHeight+10);
+}
diff --git a/src/masternode-payments.h b/src/masternode-payments.h
index c63974625..ae9b44388 100644
--- a/src/masternode-payments.h
+++ b/src/masternode-payments.h
@@ -226,6 +226,8 @@ class CMasternodePayments
 private:
     int nSyncedFromPeer;
     int nLastBlockHeight;
+    // Keep track of current block index
+    const CBlockIndex *pCurrentBlockIndex;
 
 public:
     std::map<uint256, CMasternodePaymentWinner> mapMasternodePayeeVotes;
@@ -293,6 +295,8 @@ public:
         READWRITE(mapMasternodePayeeVotes);
         READWRITE(mapMasternodeBlocks);
     }
+
+    void UpdatedBlockTip(const CBlockIndex *pindex);
 };
 
 
diff --git a/src/masternode-sync.cpp b/src/masternode-sync.cpp
index a07a6571a..701111ee3 100644
--- a/src/masternode-sync.cpp
+++ b/src/masternode-sync.cpp
@@ -42,15 +42,8 @@ bool CMasternodeSync::IsBlockchainSynced()
 
     if (fImporting || fReindex) return false;
 
-    TRY_LOCK(cs_main, lockMain);
-    if(!lockMain) return false;
-
-    CBlockIndex* pindex = chainActive.Tip();
-    if(pindex == NULL) return false;
-
-
-    if(pindex->nTime + 60*60 < GetTime())
-        return false;
+    if(!pCurrentBlockIndex) return false;
+    if(pCurrentBlockIndex->nTime + 60*60 < GetTime()) return false;
 
     fBlockchainSynced = true;
 
@@ -227,8 +220,10 @@ void CMasternodeSync::Process()
     static int tick = 0;
     if(tick++ % 6 != 0) return;
 
+    if(!pCurrentBlockIndex) return;
+
     //the actual count of masternodes we have currently
-    int nMnCount = mnodeman.CountEnabled();  
+    int nMnCount = mnodeman.CountEnabled();
 
     // RESET SYNCING INCASE OF FAILURE
     {
@@ -319,8 +314,8 @@ void CMasternodeSync::Process()
 
                 // shall we move onto the next asset?
 
-                //printf("Masternode count %d est %d\n", nMnCount, mnodeman.GetEstimatedMasternodes(chainActive.Height())) ;             
-                if(nMnCount > mnodeman.GetEstimatedMasternodes(chainActive.Height())*0.9)
+                //printf("Masternode count %d est %d\n", nMnCount, mnodeman.GetEstimatedMasternodes(pCurrentBlockIndex->nHeight));
+                if(nMnCount > mnodeman.GetEstimatedMasternodes(pCurrentBlockIndex->nHeight)*0.9)
                 {
                     GetNextAsset();
                     //printf("synced masternode list successfully\n");
@@ -378,9 +373,6 @@ void CMasternodeSync::Process()
                 if(pnode->HasFulfilledRequest("mnwsync")) continue;
                 pnode->FulfilledRequest("mnwsync");
 
-                CBlockIndex* pindexPrev = chainActive.Tip();
-                if(pindexPrev == NULL) return;
-
                 int nMnCount = mnodeman.CountEnabled();
                 pnode->PushMessage(NetMsgType::MNWINNERSSYNC, nMnCount); //sync payees
                 RequestedMasternodeAttempt++;
@@ -435,3 +427,8 @@ void CMasternodeSync::Process()
         }
     }
 }
+
+void CMasternodeSync::UpdatedBlockTip(const CBlockIndex *pindex)
+{
+    pCurrentBlockIndex = pindex;
+}
diff --git a/src/masternode-sync.h b/src/masternode-sync.h
index 3005ab6b4..647d0cc1c 100644
--- a/src/masternode-sync.h
+++ b/src/masternode-sync.h
@@ -55,6 +55,9 @@ public:
     // Time when current masternode asset sync started
     int64_t nAssetSyncStarted;
 
+    // Keep track of current block index
+    const CBlockIndex *pCurrentBlockIndex;
+
     CMasternodeSync();
 
     void AddedMasternodeList(uint256 hash);
@@ -71,6 +74,8 @@ public:
     bool IsSynced();
     bool IsBlockchainSynced();
     void ClearFulfilledRequest();
+
+    void UpdatedBlockTip(const CBlockIndex *pindex);
 };
 
 #endif
diff --git a/src/masternode.cpp b/src/masternode.cpp
index d1d76cd66..93349d660 100644
--- a/src/masternode.cpp
+++ b/src/masternode.cpp
@@ -21,6 +21,7 @@ std::map<int64_t, uint256> mapCacheBlockHashes;
 //Get the last hash that matches the modulus given. Processed in reverse order
 bool GetBlockHash(uint256& hash, int nBlockHeight)
 {
+    LOCK(cs_main);
     if (chainActive.Tip() == NULL) return false;
 
     if(nBlockHeight == 0)
@@ -151,7 +152,10 @@ bool CMasternode::UpdateFromNewBroadcast(CMasternodeBroadcast& mnb)
 //
 uint256 CMasternode::CalculateScore(int mod, int64_t nBlockHeight)
 {
-    if(chainActive.Tip() == NULL) return uint256();
+    {
+        LOCK(cs_main);
+        if(chainActive.Tip() == NULL) return uint256();
+    }
 
     uint256 hash = uint256();
     uint256 aux = ArithToUint256(UintToArith256(vin.prevout.hash) + vin.prevout.n);
@@ -241,8 +245,13 @@ int64_t CMasternode::SecondsSincePayment() {
 }
 
 int64_t CMasternode::GetLastPaid() {
-    CBlockIndex* pindexPrev = chainActive.Tip();
-    if(pindexPrev == NULL) return false;
+    CBlockIndex *pindexPrev = NULL;
+    {
+        LOCK(cs_main);
+        pindexPrev = chainActive.Tip();
+        if(!pindexPrev) return 0;
+    }
+
 
     CScript mnpayee;
     mnpayee = GetScriptForDestination(pubkey.GetID());
@@ -255,9 +264,7 @@ int64_t CMasternode::GetLastPaid() {
     // use a deterministic offset to break a tie -- 2.5 minutes
     int64_t nOffset = UintToArith256(hash).GetCompact(false) % 150;
 
-    if (chainActive.Tip() == NULL) return false;
-
-    const CBlockIndex *BlockReading = chainActive.Tip();
+    const CBlockIndex *BlockReading = pindexPrev;
 
     int nMnCount = mnodeman.CountEnabled()*1.25;
     int n = 0;
@@ -473,19 +480,21 @@ bool CMasternodeBroadcast::CheckInputsAndAdd(int& nDoS)
     uint256 hashBlock = uint256();
     CTransaction tx2;
     GetTransaction(vin.prevout.hash, tx2, Params().GetConsensus(), hashBlock, true);
-    BlockMap::iterator mi = mapBlockIndex.find(hashBlock);
-    if (mi != mapBlockIndex.end() && (*mi).second)
     {
-        CBlockIndex* pMNIndex = (*mi).second; // block for 1000 DASH tx -> 1 confirmation
-        CBlockIndex* pConfIndex = chainActive[pMNIndex->nHeight + MASTERNODE_MIN_CONFIRMATIONS - 1]; // block where tx got MASTERNODE_MIN_CONFIRMATIONS
-        if(pConfIndex->GetBlockTime() > sigTime)
+        LOCK(cs_main);
+        BlockMap::iterator mi = mapBlockIndex.find(hashBlock);
+        if (mi != mapBlockIndex.end() && (*mi).second)
         {
-            LogPrintf("mnb - Bad sigTime %d for Masternode %20s %105s (%i conf block is at %d)\n",
-                      sigTime, addr.ToString(), vin.ToString(), MASTERNODE_MIN_CONFIRMATIONS, pConfIndex->GetBlockTime());
-            return false;
+            CBlockIndex* pMNIndex = (*mi).second; // block for 1000 DASH tx -> 1 confirmation
+            CBlockIndex* pConfIndex = chainActive[pMNIndex->nHeight + MASTERNODE_MIN_CONFIRMATIONS - 1]; // block where tx got MASTERNODE_MIN_CONFIRMATIONS
+            if(pConfIndex->GetBlockTime() > sigTime)
+            {
+                LogPrintf("mnb - Bad sigTime %d for Masternode %20s %105s (%i conf block is at %d)\n",
+                          sigTime, addr.ToString(), vin.ToString(), MASTERNODE_MIN_CONFIRMATIONS, pConfIndex->GetBlockTime());
+                return false;
+            }
         }
     }
-
     LogPrintf("mnb - Got NEW Masternode entry - %s - %s - %s - %lli \n", GetHash().ToString(), addr.ToString(), vin.ToString(), sigTime);
     CMasternode mn(*this);
     mnodeman.Add(mn);
@@ -543,8 +552,17 @@ CMasternodePing::CMasternodePing()
 
 CMasternodePing::CMasternodePing(CTxIn& newVin)
 {
+    int nHeight;
+    {
+        LOCK(cs_main);
+        CBlockIndex* pindexPrev = chainActive.Tip();
+        if(!pindexPrev) return;
+
+        nHeight = pindexPrev->nHeight;
+    }
+
     vin = newVin;
-    blockHash = chainActive[chainActive.Height() - 12]->GetBlockHash();
+    blockHash = chainActive[nHeight - 12]->GetBlockHash();
     sigTime = GetAdjustedTime();
     vchSig = std::vector<unsigned char>();
 }
@@ -608,25 +626,27 @@ bool CMasternodePing::CheckAndUpdate(int& nDos, bool fRequireEnabled)
                 return false;
             }
 
-            BlockMap::iterator mi = mapBlockIndex.find(blockHash);
-            if (mi != mapBlockIndex.end() && (*mi).second)
             {
-                if((*mi).second->nHeight < chainActive.Height() - 24)
+                LOCK(cs_main);
+                BlockMap::iterator mi = mapBlockIndex.find(blockHash);
+                if (mi != mapBlockIndex.end() && (*mi).second)
                 {
-                    LogPrintf("CMasternodePing::CheckAndUpdate - Masternode %s block hash %s is too old\n", vin.ToString(), blockHash.ToString());
-                    // Do nothing here (no Masternode update, no mnping relay)
-                    // Let this node to be visible but fail to accept mnping
+                    if((*mi).second->nHeight < chainActive.Height() - 24)
+                    {
+                        LogPrintf("CMasternodePing::CheckAndUpdate - Masternode %s block hash %s is too old\n", vin.ToString(), blockHash.ToString());
+                        // Do nothing here (no Masternode update, no mnping relay)
+                        // Let this node to be visible but fail to accept mnping
+
+                        return false;
+                    }
+                } else {
+                    if (fDebug) LogPrintf("CMasternodePing::CheckAndUpdate - Masternode %s block hash %s is unknown\n", vin.ToString(), blockHash.ToString());
+                    // maybe we stuck so we shouldn't ban this node, just fail to accept it
+                    // TODO: or should we also request this block?
 
                     return false;
                 }
-            } else {
-                if (fDebug) LogPrintf("CMasternodePing::CheckAndUpdate - Masternode %s block hash %s is unknown\n", vin.ToString(), blockHash.ToString());
-                // maybe we stuck so we shouldn't ban this node, just fail to accept it
-                // TODO: or should we also request this block?
-
-                return false;
             }
-
             pmn->lastPing = *this;
 
             //mnodeman.mapSeenMasternodeBroadcast.lastPing is probably outdated, so we'll update it
diff --git a/src/masternode.h b/src/masternode.h
index 183faf875..d438baec6 100644
--- a/src/masternode.h
+++ b/src/masternode.h
@@ -251,6 +251,7 @@ public:
 
     int GetMasternodeInputAge()
     {
+        LOCK(cs_main);
         if(chainActive.Tip() == NULL) return 0;
 
         if(cacheInputAge == 0){
@@ -258,7 +259,7 @@ public:
             cacheInputAgeBlock = chainActive.Tip()->nHeight;
         }
 
-        return cacheInputAge+(chainActive.Tip()->nHeight-cacheInputAgeBlock);
+        return cacheInputAge + (chainActive.Tip()->nHeight - cacheInputAgeBlock);
     }
 
     std::string Status() {
diff --git a/src/qt/overviewpage.cpp b/src/qt/overviewpage.cpp
index 78fd819b3..6162a08f3 100644
--- a/src/qt/overviewpage.cpp
+++ b/src/qt/overviewpage.cpp
@@ -351,9 +351,6 @@ void OverviewPage::updateDarksendProgress()
     double nAverageAnonymizedRounds;
 
     {
-        TRY_LOCK(cs_main, lockMain);
-        if(!lockMain) return;
-
         nDenominatedConfirmedBalance = pwalletMain->GetDenominatedBalance();
         nDenominatedUnconfirmedBalance = pwalletMain->GetDenominatedBalance(true);
         nAnonymizableBalance = pwalletMain->GetAnonymizableBalance();
@@ -434,12 +431,10 @@ void OverviewPage::updateDarksendProgress()
 
 void OverviewPage::darkSendStatus()
 {
-    if (!chainActive.Tip()) return;
     if(!masternodeSync.IsBlockchainSynced() || ShutdownRequested()) return;
 
     static int64_t nLastDSProgressBlockTime = 0;
-
-    int nBestHeight = chainActive.Tip()->nHeight;
+    int nBestHeight = clientModel->getNumBlocks();
 
     // we we're processing more then 1 block per second, we'll just leave
     if(((nBestHeight - darkSendPool.cachedNumBlocks) / (GetTimeMillis() - nLastDSProgressBlockTime + 1) > 1)) return;
diff --git a/src/qt/sendcoinsdialog.cpp b/src/qt/sendcoinsdialog.cpp
index 422e59aff..ff59a95d4 100644
--- a/src/qt/sendcoinsdialog.cpp
+++ b/src/qt/sendcoinsdialog.cpp
@@ -583,9 +583,6 @@ void SendCoinsDialog::setBalance(const CAmount& balance, const CAmount& unconfir
 
 void SendCoinsDialog::updateDisplayUnit()
 {
-    TRY_LOCK(cs_main, lockMain);
-    if(!lockMain) return;
-
     setBalance(model->getBalance(), model->getUnconfirmedBalance(), model->getImmatureBalance(), model->getAnonymizedBalance(),
                    model->getWatchBalance(), model->getWatchUnconfirmedBalance(), model->getWatchImmatureBalance());
     CoinControlDialog::coinControl->useDarkSend = ui->checkUseDarksend->isChecked();
diff --git a/src/qt/walletmodel.cpp b/src/qt/walletmodel.cpp
index 88679e541..9896ee566 100644
--- a/src/qt/walletmodel.cpp
+++ b/src/qt/walletmodel.cpp
@@ -146,9 +146,6 @@ void WalletModel::pollBalanceChanged()
 
 void WalletModel::checkBalanceChanged()
 {
-    TRY_LOCK(cs_main, lockMain);
-    if(!lockMain) return;
-
     CAmount newBalance = getBalance();
     CAmount newUnconfirmedBalance = getUnconfirmedBalance();
     CAmount newImmatureBalance = getImmatureBalance();
diff --git a/src/rpcmasternode-budget.cpp b/src/rpcmasternode-budget.cpp
index 5685969fb..e3de83dfa 100644
--- a/src/rpcmasternode-budget.cpp
+++ b/src/rpcmasternode-budget.cpp
@@ -53,19 +53,21 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
 
     if(strCommand == "nextblock")
     {
-        CBlockIndex* pindexPrev = chainActive.Tip();
-        if(!pindexPrev) return "unknown";
+        LOCK(cs_main);
+        CBlockIndex* pindex = chainActive.Tip();
+        if(!pindex) return "unknown";
 
-        int nNext = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+        int nNext = pindex->nHeight - pindex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
         return nNext;
     }
 
     if(strCommand == "nextsuperblocksize")
     {
-        CBlockIndex* pindexPrev = chainActive.Tip();
-        if(!pindexPrev) return "unknown";
+        LOCK(cs_main);
+        CBlockIndex* pindex = chainActive.Tip();
+        if(!pindex) return "unknown";
 
-        int nHeight = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+        int nHeight = pindex->nHeight - pindex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
 
         CAmount nTotal = budget.GetTotalBudget(nHeight);
         return nTotal;
@@ -77,7 +79,8 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
             throw runtime_error("Correct usage is 'mnbudget prepare <proposal-name> <url> <payment-count> <block-start> <dash-address> <monthly-payment-dash>'");
 
         int nBlockMin = 0;
-        CBlockIndex* pindexPrev = chainActive.Tip();
+        LOCK(cs_main);
+        CBlockIndex* pindex = chainActive.Tip();
 
         std::vector<CMasternodeConfig::CMasternodeEntry> mnEntries;
         mnEntries = masternodeConfig.getEntries();
@@ -88,7 +91,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
         int nBlockStart = params[4].get_int();
 
         //set block min
-        if(pindexPrev != NULL) nBlockMin = pindexPrev->nHeight;
+        if(pindex != NULL) nBlockMin = pindex->nHeight;
 
         if(nBlockStart < nBlockMin)
             return "Invalid block start, must be more than current height.";
@@ -107,7 +110,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
         CBudgetProposalBroadcast budgetProposalBroadcast(strProposalName, strURL, nPaymentCount, scriptPubKey, nAmount, nBlockStart, uint256());
 
         std::string strError = "";
-        if(!budgetProposalBroadcast.IsValid(strError, false))
+        if(!budgetProposalBroadcast.IsValid(pindex, strError, false))
             return "Proposal is not valid - " + budgetProposalBroadcast.GetHash().ToString() + " - " + strError;
 
         bool useIX = false; //true;
@@ -140,7 +143,8 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
         }
 
         int nBlockMin = 0;
-        CBlockIndex* pindexPrev = chainActive.Tip();
+        LOCK(cs_main);
+        CBlockIndex* pindex = chainActive.Tip();
 
         std::vector<CMasternodeConfig::CMasternodeEntry> mnEntries;
         mnEntries = masternodeConfig.getEntries();
@@ -151,7 +155,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
         int nBlockStart = params[4].get_int();
 
         //set block min
-        if(pindexPrev != NULL) nBlockMin = pindexPrev->nHeight;
+        if(pindex != NULL) nBlockMin = pindex->nHeight;
 
         if(nBlockStart < nBlockMin)
             return "Invalid payment count, must be more than current height.";
@@ -170,7 +174,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
 
         std::string strError = "";
 
-        if(!budgetProposalBroadcast.IsValid(strError)){
+        if(!budgetProposalBroadcast.IsValid(pindex, strError)){
             return "Proposal is not valid - " + budgetProposalBroadcast.GetHash().ToString() + " - " + strError;
         }
 
@@ -404,6 +408,12 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
 
     if(strCommand == "projection")
     {
+        CBlockIndex* pindex;
+        {
+            LOCK(cs_main);
+            pindex = chainActive.Tip();
+        }
+
         UniValue resultObj(UniValue::VOBJ);
         CAmount nTotalAllotted = 0;
 
@@ -434,7 +444,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
             bObj.push_back(Pair("Alloted",  ValueFromAmount(pbudgetProposal->GetAllotted())));
 
             std::string strError = "";
-            bObj.push_back(Pair("IsValid",  pbudgetProposal->IsValid(strError)));
+            bObj.push_back(Pair("IsValid",  pbudgetProposal->IsValid(pindex, strError)));
             bObj.push_back(Pair("IsValidReason",  strError.c_str()));
             bObj.push_back(Pair("fValid",  pbudgetProposal->fValid));
 
@@ -453,6 +463,12 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
         std::string strShow = "valid";
         if (params.size() == 2) strShow = params[1].get_str();
 
+        CBlockIndex* pindex;
+        {
+            LOCK(cs_main);
+            pindex = chainActive.Tip();
+        }
+
         UniValue resultObj(UniValue::VOBJ);
         int64_t nTotalAllotted = 0;
 
@@ -488,7 +504,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
             bObj.push_back(Pair("IsEstablished",  pbudgetProposal->IsEstablished()));
 
             std::string strError = "";
-            bObj.push_back(Pair("IsValid",  pbudgetProposal->IsValid(strError)));
+            bObj.push_back(Pair("IsValid",  pbudgetProposal->IsValid(pindex, strError)));
             bObj.push_back(Pair("IsValidReason",  strError.c_str()));
             bObj.push_back(Pair("fValid",  pbudgetProposal->fValid));
 
@@ -544,6 +560,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
         ExtractDestination(pbudgetProposal->GetPayee(), address1);
         CBitcoinAddress address2(address1);
 
+        LOCK(cs_main);
         UniValue obj(UniValue::VOBJ);
         obj.push_back(Pair("Name",  pbudgetProposal->GetName()));
         obj.push_back(Pair("Hash",  pbudgetProposal->GetHash().ToString()));
@@ -565,7 +582,7 @@ UniValue mnbudget(const UniValue& params, bool fHelp)
         obj.push_back(Pair("IsEstablished",  pbudgetProposal->IsEstablished()));
 
         std::string strError = "";
-        obj.push_back(Pair("IsValid",  pbudgetProposal->IsValid(strError)));
+        obj.push_back(Pair("IsValid",  pbudgetProposal->IsValid(chainActive.Tip(), strError)));
         obj.push_back(Pair("fValid",  pbudgetProposal->fValid));
 
         return obj;
@@ -803,6 +820,7 @@ UniValue mnfinalbudget(const UniValue& params, bool fHelp)
         UniValue resultObj(UniValue::VOBJ);
 
         std::vector<CFinalizedBudget*> winningFbs = budget.GetFinalizedBudgets();
+        LOCK(cs_main);
         BOOST_FOREACH(CFinalizedBudget* finalizedBudget, winningFbs)
         {
             UniValue bObj(UniValue::VOBJ);
@@ -815,7 +833,7 @@ UniValue mnfinalbudget(const UniValue& params, bool fHelp)
             bObj.push_back(Pair("Status",  finalizedBudget->GetStatus()));
 
             std::string strError = "";
-            bObj.push_back(Pair("IsValid",  finalizedBudget->IsValid(strError)));
+            bObj.push_back(Pair("IsValid",  finalizedBudget->IsValid(chainActive.Tip(), strError)));
             bObj.push_back(Pair("IsValidReason",  strError.c_str()));
 
             resultObj.push_back(Pair(finalizedBudget->GetName(), bObj));
@@ -887,11 +905,11 @@ UniValue mnfinalbudget(const UniValue& params, bool fHelp)
             return "Invalid finalized proposal";
         }
 
+        LOCK(cs_main);
+        CBlockIndex* pindex = chainActive.Tip();
+        if(!pindex) return "invalid chaintip";
 
-        CBlockIndex* pindexPrev = chainActive.Tip();
-        if(!pindexPrev) return "invalid chaintip";
-
-        int nBlockStart = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+        int nBlockStart = pindex->nHeight - pindex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
 
         CFinalizedBudgetBroadcast tempBudget("main", nBlockStart, vecTxBudgetPayments, uint256());
         // if(mapSeenFinalizedBudgets.count(tempBudget.GetHash())) {
@@ -945,10 +963,11 @@ UniValue mnfinalbudget(const UniValue& params, bool fHelp)
             return "Invalid finalized proposal";
         }
 
-        CBlockIndex* pindexPrev = chainActive.Tip();
-        if(!pindexPrev) return "invalid chaintip";
+        LOCK(cs_main);
+        CBlockIndex* pindex = chainActive.Tip();
+        if(!pindex) return "invalid chaintip";
 
-        int nBlockStart = pindexPrev->nHeight - pindexPrev->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
+        int nBlockStart = pindex->nHeight - pindex->nHeight % Params().GetConsensus().nBudgetPaymentsCycleBlocks + Params().GetConsensus().nBudgetPaymentsCycleBlocks;
       
         // CTxIn in(COutPoint(nColHash, 0));
         // int conf = GetInputAgeIX(nColHash, in);
@@ -965,7 +984,7 @@ UniValue mnfinalbudget(const UniValue& params, bool fHelp)
         CFinalizedBudgetBroadcast finalizedBudgetBroadcast("main", nBlockStart, vecTxBudgetPayments, nColHash);
 
         std::string strError = "";
-        if(!finalizedBudgetBroadcast.IsValid(strError)){
+        if(!finalizedBudgetBroadcast.IsValid(pindex, strError)){
             printf("CBudgetManager::SubmitFinalBudget - Invalid finalized budget - %s \n", strError.c_str());
             return "invalid finalized budget";
         }
diff --git a/src/rpcmasternode.cpp b/src/rpcmasternode.cpp
index 1cbfef9f3..c9e147fdd 100644
--- a/src/rpcmasternode.cpp
+++ b/src/rpcmasternode.cpp
@@ -155,8 +155,11 @@ UniValue masternode(const UniValue& params, bool fHelp)
         {
             int nCount = 0;
 
-            if(chainActive.Tip())
-                mnodeman.GetNextMasternodeInQueueForPayment(chainActive.Tip()->nHeight, true, nCount);
+            {
+                LOCK(cs_main);
+                if(chainActive.Tip())
+                    mnodeman.GetNextMasternodeInQueueForPayment(chainActive.Tip()->nHeight, true, nCount);
+            }
 
             if(params[1].get_str() == "ds") return mnodeman.CountEnabled(MIN_POOL_PEER_PROTO_VERSION);
             if(params[1].get_str() == "enabled") return mnodeman.CountEnabled();
@@ -172,7 +175,10 @@ UniValue masternode(const UniValue& params, bool fHelp)
 
     if (strCommand == "current")
     {
-        CMasternode* winner = mnodeman.GetCurrentMasterNode(1);
+        LOCK(cs_main);
+        CMasternode* winner = NULL;
+        if(chainActive.Tip())
+            winner = mnodeman.GetCurrentMasterNode(1);
         if(winner) {
             UniValue obj(UniValue::VOBJ);
 
@@ -425,6 +431,15 @@ UniValue masternode(const UniValue& params, bool fHelp)
 
     if (strCommand == "winners")
     {
+        int nHeight;
+        {
+            LOCK(cs_main);
+            CBlockIndex* pindex = chainActive.Tip();
+            if(!pindex) return NullUniValue;
+
+            nHeight = pindex->nHeight;
+        }
+
         int nLast = 10;
 
         if (params.size() >= 2){
@@ -433,9 +448,9 @@ UniValue masternode(const UniValue& params, bool fHelp)
 
         UniValue obj(UniValue::VOBJ);
 
-        for(int nHeight = chainActive.Tip()->nHeight-nLast; nHeight < chainActive.Tip()->nHeight+20; nHeight++)
+        for(int i = nHeight - nLast; i < nHeight + 20; i++)
         {
-            obj.push_back(Pair(strprintf("%d", nHeight), GetRequiredPaymentsString(nHeight)));
+            obj.push_back(Pair(strprintf("%d", i), GetRequiredPaymentsString(i)));
         }
 
         return obj;
@@ -447,6 +462,15 @@ UniValue masternode(const UniValue& params, bool fHelp)
     if (strCommand == "calcscore")
     {
 
+        int nHeight;
+        {
+            LOCK(cs_main);
+            CBlockIndex* pindex = chainActive.Tip();
+            if(!pindex) return NullUniValue;
+
+            nHeight = pindex->nHeight;
+        }
+
         int nLast = 10;
 
         if (params.size() >= 2){
@@ -455,18 +479,18 @@ UniValue masternode(const UniValue& params, bool fHelp)
         UniValue obj(UniValue::VOBJ);
 
         std::vector<CMasternode> vMasternodes = mnodeman.GetFullMasternodeVector();
-        for(int nHeight = chainActive.Tip()->nHeight-nLast; nHeight < chainActive.Tip()->nHeight+20; nHeight++){
+        for(int i = nHeight - nLast; i < nHeight + 20; i++){
             arith_uint256 nHigh = 0;
             CMasternode *pBestMasternode = NULL;
             BOOST_FOREACH(CMasternode& mn, vMasternodes) {
-                arith_uint256 n = UintToArith256(mn.CalculateScore(1, nHeight-100));
+                arith_uint256 n = UintToArith256(mn.CalculateScore(1, i - 100));
                 if(n > nHigh){
                     nHigh = n;
                     pBestMasternode = &mn;
                 }
             }
             if(pBestMasternode)
-                obj.push_back(Pair(strprintf("%d", nHeight), pBestMasternode->vin.prevout.ToStringShort().c_str()));
+                obj.push_back(Pair(strprintf("%d", i), pBestMasternode->vin.prevout.ToStringShort().c_str()));
         }
 
         return obj;
diff --git a/src/spork.cpp b/src/spork.cpp
index a1ff43b8e..51d291cbc 100644
--- a/src/spork.cpp
+++ b/src/spork.cpp
@@ -39,6 +39,7 @@ void ProcessSpork(CNode* pfrom, std::string& strCommand, CDataStream& vRecv)
         CSporkMessage spork;
         vRecv >> spork;
 
+        LOCK(cs_main);
         if(chainActive.Tip() == NULL) return;
 
         uint256 hash = spork.GetHash();
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index d9aba92de..a4fd060e6 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -8,6 +8,7 @@
 #include "consensus/merkle.h"
 #include "consensus/validation.h"
 #include "main.h"
+#include "masternode-payments.h"
 #include "miner.h"
 #include "pubkey.h"
 #include "script/standard.h"
@@ -74,6 +75,9 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
     LOCK(cs_main);
     fCheckpointsEnabled = false;
 
+    // force UpdatedBlockTip to initialize pCurrentBlockIndex
+    mnpayments.UpdatedBlockTip(chainActive.Tip());
+
     // Simple block creation, nothing special yet:
     BOOST_CHECK(pblocktemplate = CreateNewBlock(chainparams, scriptPubKey));