diff --git a/iguana/iguana_blocks.c b/iguana/iguana_blocks.c
index e4b85d431..219fe020b 100755
--- a/iguana/iguana_blocks.c
+++ b/iguana/iguana_blocks.c
@@ -270,10 +270,12 @@ int32_t iguana_blockunmain(struct iguana_info *coin,struct iguana_block *block)
 struct iguana_block *_iguana_chainlink(struct iguana_info *coin,struct iguana_block *newblock)
 {
     int32_t valid,bundlei,height=-1; struct iguana_block *hwmchain,*block = 0,*prev=0,*next;
-    bits256 *hash2p=0; double prevPoW = 0.;
+    bits256 *hash2p=0; double prevPoW = 0.; struct iguana_bundle *bp;
     if ( newblock == 0 )
         return(0);
     hwmchain = &coin->blocks.hwmchain;
+    if ( hwmchain->height > 0 && ((bp= coin->current) == 0 || hwmchain->height/coin->chain->bundlesize > bp->hdrsi) )
+        return(0);
     if ( (block= iguana_blockfind(coin,newblock->RO.hash2)) != 0 )
     {
         if ( memcmp(coin->chain->genesis_hashdata,block->RO.hash2.bytes,sizeof(bits256)) == 0 )
diff --git a/iguana/iguana_bundles.c b/iguana/iguana_bundles.c
index 824ed9a57..a2204f617 100755
--- a/iguana/iguana_bundles.c
+++ b/iguana/iguana_bundles.c
@@ -227,13 +227,16 @@ int32_t iguana_bundlehash2add(struct iguana_info *coin,struct iguana_block **blo
             }
             else
             {
-//char str[65]; printf(">>>>>>>>>>>>>> bundlehash2.(%s) ht.(%d %d)\n",bits256_str(str,hash2),bp->bundleheight,bundlei);
+                char str[65];
                 block->hdrsi = bp->hdrsi;
                 block->bundlei = bundlei;
                 bp->hashes[bundlei] = block->RO.hash2;
                 if ( bp->speculative != 0 && bundlei < bp->numspec )
                     bp->speculative[bundlei] = bp->hashes[bundlei];
-                bp->blocks[bundlei] = block;
+                if ( bp->blocks[bundlei] == 0 )
+                    bp->blocks[bundlei] = block;
+                else if ( bp->blocks[bundlei] != block )
+                    printf(">>>>>>>>>>>>>> bundlehash2.(%s) ht.(%d %d) block.%p there\n",bits256_str(str,hash2),bp->bundleheight,bundlei,bp->blocks[bundlei]);
                 otherbp = 0;
                 if ( (otherbp= iguana_bundlefind(coin,&otherbp,&otherbundlei,hash2)) != 0 || (bundlei % (bundlesize-1)) == 0)
                 {
@@ -399,17 +402,9 @@ int32_t iguana_bundleissue(struct iguana_info *coin,struct iguana_bundle *bp,int
         starti = coin->current->hdrsi;
     else starti = 0;
     priority = (bp->hdrsi < starti + coin->peers.numranked);
-    /*lag = (bp->hdrsi - starti);
-    lag *= lag;
-    if ( (i= sqrt(bp->hdrsi)) < 2 )
-        i = 2;
-    if ( lag < i )
-        lag = i;
-    else if ( lag > 10*i )
-        lag = 10*i;*/
     if ( strcmp("BTC",coin->symbol) == 0 )
-        lag = 30;
-    else lag = 3;
+        lag = 30 + (bp->hdrsi - starti);
+    else lag = 3 + (bp->hdrsi - starti)/10;
     if ( (numpeers= coin->peers.numranked) > 3 )//&& bp->currentflag < bp->n )
     {
         if ( numpeers > 0xff )
@@ -517,7 +512,7 @@ int32_t iguana_bundleissue(struct iguana_info *coin,struct iguana_bundle *bp,int
                                         bp->issued[i] = block->issued = now;
                                     }
                                 }
-                                printf("slow peer.%d dead.%u (%s) reissued.%d\n",i,addr->dead,addr->ipaddr,flag);
+                                printf("slow peer.%d dead.%u (%s) reissued.%d [%d]\n",i,addr->dead,addr->ipaddr,flag,bp->hdrsi);
                             }
                         }
                     }
@@ -550,8 +545,8 @@ int32_t iguana_bundleissue(struct iguana_info *coin,struct iguana_bundle *bp,int
             if ( flag != 0 && priority != 0 && laggard != 0 && coin->current == bp )
                 printf("[%d] reissued.%d currentflag.%d ht.%d s.%d finished.%d most.%d laggards.%d maxunfinished.%d\n",bp->hdrsi,flag,bp->currentflag,bp->bundleheight,bp->numsaved,finished,doneval,laggard,maxval);
          }
-        if ( bp == coin->current )
-            return(counter);
+        //if ( bp == coin->current )
+         //   return(counter);
     }
     for (i=0; i<bp->n; i++)
     {
@@ -600,17 +595,19 @@ int32_t iguana_bundleready(struct iguana_info *coin,struct iguana_bundle *bp)
         if ( (block= bp->blocks[i]) != 0 )
         {
             //printf("(%x:%x) ",(uint32_t)block->RO.hash2.ulongs[3],(uint32_t)bp->hashes[i].ulongs[3]);
-            if ( block->fpipbits == 0 || (bp->bundleheight+i > 0 && bits256_nonz(block->RO.prev_block) == 0) || iguana_blockvalidate(coin,&valid,block,1) < 0 )
+            if ( iguana_blockvalidate(coin,&valid,block,1) < 0 || block->fpipbits == 0 || (bp->bundleheight+i > 0 && bits256_nonz(block->RO.prev_block) == 0) )
             {
-                if ( (checki= iguana_peerfname(coin,&hdrsi,GLOBALTMPDIR,fname,0,block->RO.hash2,zero,1)) == i )
+                fname[0] = 0;
+                if ( (checki= iguana_peerfname(coin,&hdrsi,GLOBALTMPDIR,fname,0,block->RO.hash2,zero,1)) != i )
+                    printf("checki.%d vs %d mismatch?\n",checki,i);
+                if ( fname[0] != 0 )
                     OS_removefile(fname,0);
-                char str[65]; printf(">>>>>>> ipbits.%x null prevblock error at ht.%d patch.(%s) and reissue %s\n",block->fpipbits,bp->bundleheight+i,bits256_str(str,block->RO.prev_block),fname);
+                char str[65]; printf(">>>>>>> ipbits.%x block contents error at ht.%d\n",bp->bundleheight+i);
+                //patch.(%s) and reissue %s checki.%d vs %d\n",block->fpipbits,bp->bundleheight+i,bits256_str(str,block->RO.prev_block),fname,checki,i);
                 block->fpipbits = 0;
                 block->fpos = -1;
                 block->queued = 0;
                 block->RO.recvlen = 0;
-                memset(bp->hashes[i].bytes,0,sizeof(bp->hashes[i]));
-                bp->blocks[i] = 0;
                 //iguana_blockQ("null retry",coin,bp,i,block->RO.hash2,1);
             } else ready++;
         } else printf("error getting block (%d:%d) %p\n",bp->hdrsi,i,block);
@@ -621,12 +618,12 @@ int32_t iguana_bundleready(struct iguana_info *coin,struct iguana_bundle *bp)
 int32_t iguana_bundlehdr(struct iguana_info *coin,struct iguana_bundle *bp,int32_t starti)
 {
     int32_t counter=0;
-    //if ( bp->speculative != 0 )
-    //    printf("hdr ITERATE bundle.%d vs %d: h.%d n.%d r.%d s.%d finished.%d speculative.%p\n",bp->bundleheight,coin->longestchain-coin->chain->bundlesize,bp->numhashes,bp->n,bp->numrecv,bp->numsaved,bp->emitfinish,bp->speculative);
     int32_t i; uint32_t now;
     if ( coin->enableCACHE != 0 && bp->speculative == 0 && bp->numhashes < bp->n )
     {
         char str[64];
+        if ( bp == coin->current )
+            printf("hdr ITERATE bundle.%d vs %d: h.%d n.%d r.%d s.%d finished.%d speculative.%p\n",bp->bundleheight,coin->longestchain-coin->chain->bundlesize,bp->numhashes,bp->n,bp->numrecv,bp->numsaved,bp->emitfinish,bp->speculative);
         queue_enqueue("hdrsQ",&coin->hdrsQ,queueitem(bits256_str(str,bp->hashes[0])),1);
     }
     if ( bp->speculative != 0 )
diff --git a/iguana/iguana_recv.c b/iguana/iguana_recv.c
index afa166a53..865b3e076 100755
--- a/iguana/iguana_recv.c
+++ b/iguana/iguana_recv.c
@@ -508,7 +508,7 @@ struct iguana_bundle *iguana_bundleset(struct iguana_info *coin,struct iguana_bl
 
 struct iguana_bundlereq *iguana_recvblockhdrs(struct iguana_info *coin,struct iguana_bundlereq *req,struct iguana_block *blocks,int32_t n,int32_t *newhwmp)
 {
-    int32_t i,bundlei,match; bits256 *blockhashes,allhash; struct iguana_block *block; struct iguana_bundle *bp,*firstbp = 0;
+    int32_t i,bundlei,match; struct iguana_block *block; struct iguana_bundle *bp,*firstbp = 0;
     if ( blocks == 0 )
     {
         printf("iguana_recvblockhdrs null blocks?\n");
@@ -516,7 +516,7 @@ struct iguana_bundlereq *iguana_recvblockhdrs(struct iguana_info *coin,struct ig
     }
     if ( blocks != 0 && n > 0 )
     {
-        if ( 0 && n >= coin->chain->bundlesize )
+        /*if ( 0 && n >= coin->chain->bundlesize )
         {
             blockhashes = malloc(sizeof(*blockhashes) * coin->chain->bundlesize);
             for (i=0; i<coin->chain->bundlesize; i++)
@@ -540,7 +540,7 @@ struct iguana_bundlereq *iguana_recvblockhdrs(struct iguana_info *coin,struct ig
                 }
             }
             free(blockhashes);
-        }
+        }*/
         for (i=match=0; i<n; i++)
         {
             //fprintf(stderr,"i.%d of %d bundleset\n",i,n);
@@ -1003,7 +1003,7 @@ int32_t iguana_reqblocks(struct iguana_info *coin)
                 if ( bits256_nonz(hash2) > 0 )
                 {
                     coin->backstopmillis = OS_milliseconds();
-                    iguana_blockQ("mainchain",coin,0,-1,hash2,lag > 100 * threshold);
+                    iguana_blockQ("mainchain",coin,0,-1,hash2,lag > threshold);
                     flag++;
                     char str[65];
                     if ( 1 && (rand() % 1000) == 0 )//|| bp->bundleheight > coin->longestchain-coin->chain->bundlesize )
@@ -1012,7 +1012,7 @@ int32_t iguana_reqblocks(struct iguana_info *coin)
                 else if ( bp != 0 && bundlei < bp->n-1 && (bits256_nonz(bp->hashes[bundlei+1]) != 0 || (bp->speculative != 0 && bits256_nonz(bp->speculative[bundlei+1]) != 0)) )
                 {
                     int32_t j;
-                    memset(bp->hashes[bundlei].bytes,0,sizeof(bp->hashes[bundlei]));
+                    //memset(bp->hashes[bundlei].bytes,0,sizeof(bp->hashes[bundlei]));
                     bp->blocks[bundlei] = 0;
                     for (j=0; j<1&&bundlei+j+1<bp->n; j++)
                     {
diff --git a/iguana/iguana_unspents.c b/iguana/iguana_unspents.c
index cd6e635db..9029fd761 100755
--- a/iguana/iguana_unspents.c
+++ b/iguana/iguana_unspents.c
@@ -387,8 +387,9 @@ int32_t iguana_spendvectors(struct iguana_info *coin,struct iguana_bundle *bp)
                             printf("unexpected spendbp: height.%d bp.[%d] U%d <- S%d.[%d] [ext.%d %s prev.%d]\n",bp->bundleheight+i,spentbp->hdrsi,spent_unspentind,spendind,bp->hdrsi,s->external,bits256_str(str,prevhash),s->prevout);
                             errs++;
                         }
-                        if ( now > spentbp->lastprefetch+60 || (spentbp->dirty % 100000) == 0 )
+                        if ( now > spentbp->lastprefetch+10 || (spentbp->dirty % 10000) == 0 )
                         {
+                            printf("prefetch[%d]\n",spentbp->hdrsi);
                             iguana_ramchain_prefetch(coin,&spentbp->ramchain);
                             spentbp->lastprefetch = now;
                         }