try

src/cc/CCtx.cpp

@@ -17,12 +17,12 @@
 
 /*
  FinalizeCCTx is a very useful function that will properly sign both CC and normal inputs, adds normal change and the opreturn.
- 
+
  This allows the contract transaction functions to create the appropriate vins and vouts and have FinalizeCCTx create a properly signed transaction.
- 
+
  By using -addressindex=1, it allows tracking of all the CC addresses
  */
- 
+
 bool SignTx(CMutableTransaction &mtx,int32_t vini,int64_t utxovalue,const CScript scriptPubKey)
 {
 #ifdef ENABLE_WALLET
@@ -274,8 +274,18 @@ int32_t CC_vinselect(int32_t *aboveip,int64_t *abovep,int32_t *belowip,int64_t *
 {
     int32_t i,abovei,belowi; int64_t above,below,gap,atx_value;
     abovei = belowi = -1;
+    int loops = 0;
+    int numtxs = numunspents/2;
+    int startfrom = rand()%numtxs;
     for (above=below=i=0; i<numunspents; i++)
     {
+        loops++;
+        if ( numunspents > 300 ) {
+            if ( loops < startfrom )
+                continue;
+            if ( (rand() % 100) < 75 )
+                continue;
+        }
         if ( (atx_value= utxos[i].nValue) <= 0 )
             continue;
         if ( atx_value == value )