diff --git a/src/engine/dispatch.h b/src/engine/dispatch.h
index 81f005140..e5ed94073 100644
--- a/src/engine/dispatch.h
+++ b/src/engine/dispatch.h
@@ -95,6 +95,10 @@ class DivEngine;
 class DivDispatch {
   protected:
     DivEngine* parent;
+    /**
+     * please honor this variable if needed.
+     */
+    bool skipRegisterWrites;
   public:
     /**
      * the rate the samples are provided.
@@ -167,6 +171,16 @@ class DivDispatch {
      */
     virtual void setPAL(bool pal);
 
+    /**
+     * set skip reg writes.
+     */
+    void setSkipRegisterWrites(bool value);
+
+    /**
+     * force-retrigger instruments.
+     */
+    virtual void forceIns();
+
     /**
      * initialize this DivDispatch.
      * @param parent the parent DivEngine.
diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index 41c7d2946..25aff9899 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -1419,15 +1419,30 @@ void DivEngine::setLoops(int loops) {
   remainingLoops=loops;
 }
 
-void DivEngine::play() {
-  isBusy.lock();
+void DivEngine::playSub() {
   reset();
+  int goal=curOrder;
+  curOrder=0;
   curRow=0;
   clockDrift=0;
   cycles=0;
   ticks=1;  
   speedAB=false;
   playing=true;
+  dispatch->setSkipRegisterWrites(true);
+  while (curOrder<goal) {
+    if (nextTick()) break;
+  }
+  dispatch->setSkipRegisterWrites(false);
+  dispatch->forceIns();
+  clockDrift=0;
+  cycles=0;
+  ticks=1; 
+}
+
+void DivEngine::play() {
+  isBusy.lock();
+  playSub();
   isBusy.unlock();
 }
 
@@ -1667,12 +1682,7 @@ void DivEngine::setOrder(unsigned char order) {
   curOrder=order;
   if (order>=song.ordersLen) curOrder=0;
   if (playing) {
-    reset();
-    curRow=0;
-    clockDrift=0;
-    cycles=0;
-    ticks=1;
-    speedAB=false;
+    playSub();
   }
   isBusy.unlock();
 }
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 0f8584516..329968900 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -113,6 +113,7 @@ class DivEngine {
   bool perSystemPostEffect(int ch, unsigned char effect, unsigned char effectVal);
   void renderSamples();
   void reset();
+  void playSub();
 
   public:
     DivSong song;
diff --git a/src/engine/platform/abstract.cpp b/src/engine/platform/abstract.cpp
index 7012cc5db..8f5ad455a 100644
--- a/src/engine/platform/abstract.cpp
+++ b/src/engine/platform/abstract.cpp
@@ -34,6 +34,14 @@ bool DivDispatch::keyOffAffectsArp(int ch) {
 void DivDispatch::setPAL(bool pal) {
 }
 
+void DivDispatch::setSkipRegisterWrites(bool value) {
+  skipRegisterWrites=value;
+}
+
+void DivDispatch::forceIns() {
+  
+}
+
 int DivDispatch::init(DivEngine* p, int channels, int sugRate, bool pal) {
   return 0;
 }
diff --git a/src/engine/platform/arcade.cpp b/src/engine/platform/arcade.cpp
index 305e83405..c3ad0c7b2 100644
--- a/src/engine/platform/arcade.cpp
+++ b/src/engine/platform/arcade.cpp
@@ -31,7 +31,8 @@ static int orderedOps[4]={
   0,2,1,3
 };
 
-#define rWrite(a,v) pendingWrites[a]=v;
+#define rWrite(a,v) if (!skipRegisterWrites) {pendingWrites[a]=v;}
+#define immWrite(a,v) if (!skipRegisterWrites) {writes.emplace(a,v);}
 
 void DivPlatformArcade::acquire_nuked(short* bufL, short* bufR, size_t start, size_t len) {
   static int o[2];
@@ -167,14 +168,14 @@ int hScale(int note) {
 void DivPlatformArcade::tick() {
   for (int i=0; i<8; i++) {
     if (chan[i].keyOn || chan[i].keyOff) {
-      writes.emplace(0x08,i);
+      immWrite(0x08,i);
       chan[i].keyOff=false;
     }
   }
 
   for (int i=0; i<256; i++) {
     if (pendingWrites[i]!=oldWrites[i]) {
-      writes.emplace(i,pendingWrites[i]&0xff);
+      immWrite(i,pendingWrites[i]&0xff);
       oldWrites[i]=pendingWrites[i];
     }
   }
@@ -182,12 +183,12 @@ void DivPlatformArcade::tick() {
   for (int i=0; i<8; i++) {
     if (chan[i].freqChanged) {
       chan[i].freq=chan[i].baseFreq+(chan[i].pitch>>1)-64;
-      writes.emplace(i+0x28,hScale(chan[i].freq>>6));
-      writes.emplace(i+0x30,chan[i].freq<<2);
+      immWrite(i+0x28,hScale(chan[i].freq>>6));
+      immWrite(i+0x30,chan[i].freq<<2);
       chan[i].freqChanged=false;
     }
     if (chan[i].keyOn) {
-      writes.emplace(0x08,0x78|i);
+      immWrite(0x08,0x78|i);
       chan[i].keyOn=false;
     }
   }
@@ -209,6 +210,7 @@ int DivPlatformArcade::dispatch(DivCommand c) {
   switch (c.cmd) {
     case DIV_CMD_NOTE_ON: {
       if (c.chan>7) {
+        if (skipRegisterWrites) break;
         chan[c.chan].pcm.sample=12*sampleBank+c.value%12;
         if (chan[c.chan].pcm.sample>=parent->song.sampleLen) {
           chan[c.chan].pcm.sample=-1;
@@ -425,6 +427,12 @@ int DivPlatformArcade::dispatch(DivCommand c) {
   return 1;
 }
 
+void DivPlatformArcade::forceIns() {
+  for (int i=0; i<13; i++) {
+    chan[i].insChanged=true;
+  }
+}
+
 void DivPlatformArcade::reset() {
   while (!writes.empty()) writes.pop();
   if (useYMFM) {
@@ -451,8 +459,8 @@ void DivPlatformArcade::reset() {
   delay=0;
 
   //rWrite(0x18,0x10);
-  writes.emplace(0x19,0x7f);
-  writes.emplace(0x19,0xff);
+  immWrite(0x19,0x7f);
+  immWrite(0x19,0xff);
   //rWrite(0x1b,0x00);
 
   extMode=false;
diff --git a/src/engine/platform/arcade.h b/src/engine/platform/arcade.h
index 43074bd31..cba403b69 100644
--- a/src/engine/platform/arcade.h
+++ b/src/engine/platform/arcade.h
@@ -64,6 +64,7 @@ class DivPlatformArcade: public DivDispatch {
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool isStereo();
diff --git a/src/engine/platform/c64.cpp b/src/engine/platform/c64.cpp
index ce6887af7..5d83fd743 100644
--- a/src/engine/platform/c64.cpp
+++ b/src/engine/platform/c64.cpp
@@ -4,6 +4,8 @@
 
 #define FREQ_BASE 277.0f
 
+#define rWrite(a,v) if (!skipRegisterWrites) {sid.write(a,v);}
+
 void DivPlatformC64::acquire(short* bufL, short* bufR, size_t start, size_t len) {
   for (size_t i=start; i<start+len; i++) {
     sid.clock();
@@ -12,10 +14,10 @@ void DivPlatformC64::acquire(short* bufL, short* bufR, size_t start, size_t len)
 }
 
 void DivPlatformC64::updateFilter() {
-  sid.write(0x15,filtCut&7);
-  sid.write(0x16,filtCut>>3);
-  sid.write(0x17,(filtRes<<4)|(chan[2].filter<<2)|(chan[1].filter<<1)|(chan[0].filter));
-  sid.write(0x18,(filtControl<<4)|vol);
+  rWrite(0x15,filtCut&7);
+  rWrite(0x16,filtCut>>3);
+  rWrite(0x17,(filtRes<<4)|(chan[2].filter<<2)|(chan[1].filter<<1)|(chan[0].filter));
+  rWrite(0x18,(filtControl<<4)|vol);
 }
 
 void DivPlatformC64::tick() {
@@ -50,37 +52,37 @@ void DivPlatformC64::tick() {
     }
     if (chan[i].std.hadDuty) {
       chan[i].duty-=((signed char)chan[i].std.duty-12)*4;
-      sid.write(i*7+2,chan[i].duty&0xff);
-      sid.write(i*7+3,chan[i].duty>>8);
+      rWrite(i*7+2,chan[i].duty&0xff);
+      rWrite(i*7+3,chan[i].duty>>8);
     }
     if (chan[i].testWhen>0) {
       if (--chan[i].testWhen<1) {
         if (!chan[i].resetMask && !isMuted[i]) {
-          sid.write(i*7+5,0);
-          sid.write(i*7+6,0);
-          sid.write(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|8|(chan[i].ring<<2)|(chan[i].sync<<1));
+          rWrite(i*7+5,0);
+          rWrite(i*7+6,0);
+          rWrite(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|8|(chan[i].ring<<2)|(chan[i].sync<<1));
         }
       }
     }
     if (chan[i].std.hadWave) {
       chan[i].wave=chan[i].std.wave;
-      sid.write(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|(chan[i].ring<<2)|(chan[i].sync<<1)|chan[i].active);
+      rWrite(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|(chan[i].ring<<2)|(chan[i].sync<<1)|chan[i].active);
     }
     if (chan[i].freqChanged || chan[i].keyOn || chan[i].keyOff) {
       chan[i].freq=(chan[i].baseFreq*(ONE_SEMITONE+chan[i].pitch))/ONE_SEMITONE;
       if (chan[i].freq>0xffff) chan[i].freq=0xffff;
       if (chan[i].keyOn) {
-        sid.write(i*7+5,(chan[i].attack<<4)|(chan[i].decay));
-        sid.write(i*7+6,(chan[i].sustain<<4)|(chan[i].release));
-        sid.write(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|(chan[i].ring<<2)|(chan[i].sync<<1)|1);
+        rWrite(i*7+5,(chan[i].attack<<4)|(chan[i].decay));
+        rWrite(i*7+6,(chan[i].sustain<<4)|(chan[i].release));
+        rWrite(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|(chan[i].ring<<2)|(chan[i].sync<<1)|1);
       }
       if (chan[i].keyOff && !isMuted[i]) {
-        sid.write(i*7+5,(chan[i].attack<<4)|(chan[i].decay));
-        sid.write(i*7+6,(chan[i].sustain<<4)|(chan[i].release));
-        sid.write(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|(chan[i].ring<<2)|(chan[i].sync<<1)|0);
+        rWrite(i*7+5,(chan[i].attack<<4)|(chan[i].decay));
+        rWrite(i*7+6,(chan[i].sustain<<4)|(chan[i].release));
+        rWrite(i*7+4,(isMuted[i]?0:(chan[i].wave<<4))|(chan[i].ring<<2)|(chan[i].sync<<1)|0);
       }
-      sid.write(i*7,chan[i].freq&0xff);
-      sid.write(i*7+1,chan[i].freq>>8);
+      rWrite(i*7,chan[i].freq&0xff);
+      rWrite(i*7+1,chan[i].freq>>8);
       if (chan[i].keyOn) chan[i].keyOn=false;
       if (chan[i].keyOff) chan[i].keyOff=false;
       chan[i].freqChanged=false;
@@ -99,8 +101,8 @@ int DivPlatformC64::dispatch(DivCommand c) {
       chan[c.chan].keyOn=true;
       if (chan[c.chan].insChanged || chan[c.chan].resetDuty || ins->std.waveMacroLen>0) {
         chan[c.chan].duty=(ins->c64.duty*4095)/100;
-        sid.write(c.chan*7+2,chan[c.chan].duty&0xff);
-        sid.write(c.chan*7+3,chan[c.chan].duty>>8);
+        rWrite(c.chan*7+2,chan[c.chan].duty&0xff);
+        rWrite(c.chan*7+3,chan[c.chan].duty>>8);
       }
       if (chan[c.chan].insChanged) {
         chan[c.chan].wave=(ins->c64.noiseOn<<3)|(ins->c64.pulseOn<<2)|(ins->c64.sawOn<<1)|(ins->c64.triOn);
@@ -181,12 +183,12 @@ int DivPlatformC64::dispatch(DivCommand c) {
     }
     case DIV_CMD_STD_NOISE_MODE:
       chan[c.chan].duty=(c.value*4095)/100;
-      sid.write(c.chan*7+2,chan[c.chan].duty&0xff);
-      sid.write(c.chan*7+3,chan[c.chan].duty>>8);
+      rWrite(c.chan*7+2,chan[c.chan].duty&0xff);
+      rWrite(c.chan*7+3,chan[c.chan].duty>>8);
       break;
     case DIV_CMD_WAVE:
       chan[c.chan].wave=c.value;
-      sid.write(c.chan*7+4,(chan[c.chan].wave<<4)|(chan[c.chan].ring<<2)|(chan[c.chan].sync<<1)|chan[c.chan].active);
+      rWrite(c.chan*7+4,(chan[c.chan].wave<<4)|(chan[c.chan].ring<<2)|(chan[c.chan].sync<<1)|chan[c.chan].active);
       break;
     case DIV_CMD_LEGATO:
       chan[c.chan].baseFreq=round(FREQ_BASE*pow(2.0f,((float)(c.value+((chan[c.chan].std.willArp && !chan[c.chan].std.arpMode)?(chan[c.chan].std.arp-12):(0)))/12.0f)));
@@ -236,8 +238,8 @@ int DivPlatformC64::dispatch(DivCommand c) {
       if (c.value&15) {
         DivInstrument* ins=parent->getIns(chan[c.chan].ins);
         chan[c.chan].duty=(ins->c64.duty*4095)/100;
-        sid.write(c.chan*7+2,chan[c.chan].duty&0xff);
-        sid.write(c.chan*7+3,chan[c.chan].duty>>8);
+        rWrite(c.chan*7+2,chan[c.chan].duty&0xff);
+        rWrite(c.chan*7+3,chan[c.chan].duty>>8);
       }
       chan[c.chan].resetDuty=c.value>>4;
       break;
@@ -257,11 +259,11 @@ int DivPlatformC64::dispatch(DivCommand c) {
           break;
         case 4:
           chan[c.chan].ring=c.value;
-          sid.write(c.chan*7+4,(chan[c.chan].wave<<4)|(chan[c.chan].ring<<2)|(chan[c.chan].sync<<1)|chan[c.chan].active);
+          rWrite(c.chan*7+4,(chan[c.chan].wave<<4)|(chan[c.chan].ring<<2)|(chan[c.chan].sync<<1)|chan[c.chan].active);
           break;
         case 5:
           chan[c.chan].sync=c.value;
-          sid.write(c.chan*7+4,(chan[c.chan].wave<<4)|(chan[c.chan].ring<<2)|(chan[c.chan].sync<<1)|chan[c.chan].active);
+          rWrite(c.chan*7+4,(chan[c.chan].wave<<4)|(chan[c.chan].ring<<2)|(chan[c.chan].sync<<1)|chan[c.chan].active);
           break;
         case 6:
           filtControl&=7;
@@ -280,7 +282,14 @@ int DivPlatformC64::dispatch(DivCommand c) {
 
 void DivPlatformC64::muteChannel(int ch, bool mute) {
   isMuted[ch]=mute;
-  sid.write(ch*7+4,(isMuted[ch]?0:(chan[ch].wave<<4))|(chan[ch].ring<<2)|(chan[ch].sync<<1)|chan[ch].active);
+  rWrite(ch*7+4,(isMuted[ch]?0:(chan[ch].wave<<4))|(chan[ch].ring<<2)|(chan[ch].sync<<1)|chan[ch].active);
+}
+
+void DivPlatformC64::forceIns() {
+  for (int i=0; i<3; i++) {
+    chan[i].insChanged=true;
+    chan[i].testWhen=0;
+  }
 }
 
 void DivPlatformC64::reset() {
@@ -290,7 +299,7 @@ void DivPlatformC64::reset() {
 
   sid.reset();
 
-  sid.write(0x18,0x0f);
+  rWrite(0x18,0x0f);
 
   filtControl=0;
   filtRes=0;
diff --git a/src/engine/platform/c64.h b/src/engine/platform/c64.h
index 67b0a3e28..9638bd57c 100644
--- a/src/engine/platform/c64.h
+++ b/src/engine/platform/c64.h
@@ -57,6 +57,7 @@ class DivPlatformC64: public DivDispatch {
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     void setPAL(bool pal);
diff --git a/src/engine/platform/gb.cpp b/src/engine/platform/gb.cpp
index 653feb735..21e95c6f6 100644
--- a/src/engine/platform/gb.cpp
+++ b/src/engine/platform/gb.cpp
@@ -3,7 +3,7 @@
 #include <math.h>
 
 //#define rWrite(a,v) pendingWrites[a]=v;
-#define rWrite(a,v) GB_apu_write(gb,a,v);
+#define rWrite(a,v) if (!skipRegisterWrites) {GB_apu_write(gb,a,v);}
 
 #define FREQ_BASE 8015.85f
 
@@ -286,6 +286,14 @@ int DivPlatformGB::dispatch(DivCommand c) {
   return 1;
 }
 
+void DivPlatformGB::forceIns() {
+  for (int i=0; i<4; i++) {
+    chan[i].insChanged=true;
+  }
+  GB_apu_write(gb,0x25,procMute());
+  updateWave();
+}
+
 void DivPlatformGB::reset() {
   for (int i=0; i<4; i++) {
     chan[i]=DivPlatformGB::Channel();
diff --git a/src/engine/platform/gb.h b/src/engine/platform/gb.h
index 6866b3ab1..7cb9624b7 100644
--- a/src/engine/platform/gb.h
+++ b/src/engine/platform/gb.h
@@ -41,6 +41,7 @@ class DivPlatformGB: public DivDispatch {
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool isStereo();
diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 89e38fff5..dd40bfa84 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -23,9 +23,9 @@ void DivPlatformGenesis::acquire(short* bufL, short* bufR, size_t start, size_t
         DivSample* s=parent->song.sample[dacSample];
         if (!isMuted[5]) {
           if (s->depth==8) {
-            writes.emplace(0x2a,(unsigned char)s->rendData[dacPos++]+0x80);
+            immWrite(0x2a,(unsigned char)s->rendData[dacPos++]+0x80);
           } else {
-            writes.emplace(0x2a,((unsigned short)s->rendData[dacPos++]+0x8000)>>8);
+            immWrite(0x2a,((unsigned short)s->rendData[dacPos++]+0x8000)>>8);
           }
         }
         if (dacPos>=s->rendLength) {
@@ -82,14 +82,14 @@ void DivPlatformGenesis::tick() {
   for (int i=0; i<6; i++) {
     if (i==2 && extMode) continue;
     if (chan[i].keyOn || chan[i].keyOff) {
-      writes.emplace(0x28,0x00|konOffs[i]);
+      immWrite(0x28,0x00|konOffs[i]);
       chan[i].keyOff=false;
     }
   }
 
   for (int i=0; i<512; i++) {
     if (pendingWrites[i]!=oldWrites[i]) {
-      writes.emplace(i,pendingWrites[i]&0xff);
+      immWrite(i,pendingWrites[i]&0xff);
       oldWrites[i]=pendingWrites[i];
     }
   }
@@ -99,12 +99,12 @@ void DivPlatformGenesis::tick() {
     if (chan[i].freqChanged) {
       chan[i].freq=(chan[i].baseFreq*(ONE_SEMITONE+chan[i].pitch))/ONE_SEMITONE;
       int freqt=toFreq(chan[i].freq);
-      writes.emplace(chanOffs[i]+0xa4,freqt>>8);
-      writes.emplace(chanOffs[i]+0xa0,freqt&0xff);
+      immWrite(chanOffs[i]+0xa4,freqt>>8);
+      immWrite(chanOffs[i]+0xa0,freqt&0xff);
       chan[i].freqChanged=false;
     }
     if (chan[i].keyOn) {
-      writes.emplace(0x28,0xf0|konOffs[i]);
+      immWrite(0x28,0xf0|konOffs[i]);
       chan[i].keyOn=false;
     }
   }
@@ -171,6 +171,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
   switch (c.cmd) {
     case DIV_CMD_NOTE_ON: {
       if (c.chan==5 && dacMode) {
+        if (skipRegisterWrites) break;
         dacSample=12*sampleBank+c.value%12;
         if (dacSample>=parent->song.sampleLen) {
           dacSample=-1;
@@ -370,6 +371,15 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
   return 1;
 }
 
+void DivPlatformGenesis::forceIns() {
+  for (int i=0; i<10; i++) {
+    chan[i].insChanged=true;
+  }
+  if (dacMode) {
+    rWrite(0x2b,0x80);
+  }
+}
+
 void DivPlatformGenesis::reset() {
   while (!writes.empty()) writes.pop();
   OPN2_Reset(&fm);
@@ -394,7 +404,7 @@ void DivPlatformGenesis::reset() {
   extMode=false;
 
   // LFO
-  writes.emplace(0x22,0x08);
+  immWrite(0x22,0x08);
   
   delay=0;
   
diff --git a/src/engine/platform/genesis.h b/src/engine/platform/genesis.h
index b40c87c30..427c628cd 100644
--- a/src/engine/platform/genesis.h
+++ b/src/engine/platform/genesis.h
@@ -53,6 +53,7 @@ class DivPlatformGenesis: public DivDispatch {
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool isStereo();
diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index 63aa10aaa..980e637a8 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -231,7 +231,7 @@ void DivPlatformGenesisExt::tick() {
       }
     }
     if (writeSomething) {
-      writes.emplace(0x28,writeMask);
+      immWrite(0x28,writeMask);
     }
   }
 
@@ -267,8 +267,8 @@ void DivPlatformGenesisExt::tick() {
         opChan[i].freqH=(opChan[i].freq>>8)&7;
         opChan[i].freqL=opChan[i].freq&0xff;
       }
-      writes.emplace(opChanOffsH[i],opChan[i].freqH);
-      writes.emplace(opChanOffsL[i],opChan[i].freqL);
+      immWrite(opChanOffsH[i],opChan[i].freqH);
+      immWrite(opChanOffsL[i],opChan[i].freqL);
     }
     writeMask|=opChan[i].active<<(4+i);
     if (opChan[i].keyOn) {
@@ -278,7 +278,14 @@ void DivPlatformGenesisExt::tick() {
     }
   }
   if (writeNoteOn) {
-    writes.emplace(0x28,writeMask);
+    immWrite(0x28,writeMask);
+  }
+}
+
+void DivPlatformGenesisExt::forceIns() {
+  DivPlatformGenesis::forceIns();
+  for (int i=0; i<4; i++) {
+    opChan[i].insChanged=true;
   }
 }
 
@@ -291,7 +298,7 @@ void DivPlatformGenesisExt::reset() {
   }
 
   // channel 3 mode
-  writes.emplace(0x27,0x40);
+  immWrite(0x27,0x40);
   extMode=true;
 }
 
diff --git a/src/engine/platform/genesisext.h b/src/engine/platform/genesisext.h
index 506a3e66b..de77c085f 100644
--- a/src/engine/platform/genesisext.h
+++ b/src/engine/platform/genesisext.h
@@ -18,6 +18,7 @@ class DivPlatformGenesisExt: public DivPlatformGenesis {
   public:
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool keyOffAffectsArp(int ch);
diff --git a/src/engine/platform/genesisshared.h b/src/engine/platform/genesisshared.h
index cf0047e70..5036f3ed1 100644
--- a/src/engine/platform/genesisshared.h
+++ b/src/engine/platform/genesisshared.h
@@ -23,4 +23,5 @@ static int orderedOps[4]={
   0,2,1,3
 };
 
-#define rWrite(a,v) pendingWrites[a]=v;
+#define rWrite(a,v) if (!skipRegisterWrites) {pendingWrites[a]=v;}
+#define immWrite(a,v) if (!skipRegisterWrites) {writes.emplace(a,v);}
diff --git a/src/engine/platform/nes.cpp b/src/engine/platform/nes.cpp
index a26c24072..6575bf7b8 100644
--- a/src/engine/platform/nes.cpp
+++ b/src/engine/platform/nes.cpp
@@ -6,6 +6,8 @@
 #define FREQ_BASE 3424.0f
 #define FREQ_BASE_PAL 3180.0f
 
+#define rWrite(a,v) if (!skipRegisterWrites) {apu_wr_reg(a,v);}
+
 void DivPlatformNES::acquire(short* bufL, short* bufR, size_t start, size_t len) {
   for (size_t i=start; i<start+len; i++) {
     if (dacSample!=-1) {
@@ -14,9 +16,9 @@ void DivPlatformNES::acquire(short* bufL, short* bufR, size_t start, size_t len)
         DivSample* s=parent->song.sample[dacSample];
         if (!isMuted[4]) {
           if (s->depth==8) {
-            apu_wr_reg(0x4011,((unsigned char)s->rendData[dacPos++]+0x80)>>1);
+            rWrite(0x4011,((unsigned char)s->rendData[dacPos++]+0x80)>>1);
           } else {
-            apu_wr_reg(0x4011,((unsigned short)s->rendData[dacPos++]+0x8000)>>9);
+            rWrite(0x4011,((unsigned short)s->rendData[dacPos++]+0x8000)>>9);
           }
         }
         if (dacPos>=s->rendLength) {
@@ -72,10 +74,10 @@ void DivPlatformNES::tick() {
       chan[i].outVol=chan[i].std.vol-(15-chan[i].vol);
       if (chan[i].outVol<0) chan[i].outVol=0;
       if (i==2) { // triangle
-        apu_wr_reg(0x4000+i*4,(chan[i].outVol==0)?0:255);
+        rWrite(0x4000+i*4,(chan[i].outVol==0)?0:255);
         chan[i].freqChanged=true;
       } else {
-        apu_wr_reg(0x4000+i*4,0x30|chan[i].outVol|((chan[i].duty&3)<<6));
+        rWrite(0x4000+i*4,0x30|chan[i].outVol|((chan[i].duty&3)<<6));
       }
     }
     if (chan[i].std.hadArp) {
@@ -107,7 +109,7 @@ void DivPlatformNES::tick() {
       chan[i].duty=chan[i].std.duty;
       if (i==3 && chan[i].duty>1) chan[i].duty=1;
       if (i!=2) {
-        apu_wr_reg(0x4000+i*4,0x30|chan[i].outVol|((chan[i].duty&3)<<6));
+        rWrite(0x4000+i*4,0x30|chan[i].outVol|((chan[i].duty&3)<<6));
       }
       if (i==3) { // noise
         chan[i].freqChanged=true;
@@ -133,18 +135,18 @@ void DivPlatformNES::tick() {
       if (chan[i].keyOff) {
         //rWrite(16+i*5+2,8);
         if (i==2) { // triangle
-          apu_wr_reg(0x4000+i*4,0x00);
+          rWrite(0x4000+i*4,0x00);
         } else {
-          apu_wr_reg(0x4000+i*4,0x30);
+          rWrite(0x4000+i*4,0x30);
         }
       }
       if (i==3) { // noise
-        apu_wr_reg(0x4002+i*4,(chan[i].duty<<7)|chan[i].freq);
-        apu_wr_reg(0x4003+i*4,0xf0);
+        rWrite(0x4002+i*4,(chan[i].duty<<7)|chan[i].freq);
+        rWrite(0x4003+i*4,0xf0);
       } else {
-        apu_wr_reg(0x4002+i*4,chan[i].freq&0xff);
+        rWrite(0x4002+i*4,chan[i].freq&0xff);
         if ((chan[i].prevFreq>>8)!=(chan[i].freq>>8) || i==2) {
-          apu_wr_reg(0x4003+i*4,0xf8|(chan[i].freq>>8));
+          rWrite(0x4003+i*4,0xf8|(chan[i].freq>>8));
         }
         if (chan[i].freq!=65535 && chan[i].freq!=0) {
           chan[i].prevFreq=chan[i].freq;
@@ -181,9 +183,9 @@ int DivPlatformNES::dispatch(DivCommand c) {
       chan[c.chan].keyOn=true;
       chan[c.chan].std.init(parent->getIns(chan[c.chan].ins));
       if (c.chan==2) {
-        apu_wr_reg(0x4000+c.chan*4,0xff);
+        rWrite(0x4000+c.chan*4,0xff);
       } else {
-        apu_wr_reg(0x4000+c.chan*4,0x30|chan[c.chan].vol|((chan[c.chan].duty&3)<<6));
+        rWrite(0x4000+c.chan*4,0x30|chan[c.chan].vol|((chan[c.chan].duty&3)<<6));
       }
       break;
     case DIV_CMD_NOTE_OFF:
@@ -204,9 +206,9 @@ int DivPlatformNES::dispatch(DivCommand c) {
           chan[c.chan].outVol=c.value;
         }
         if (c.chan==2) {
-          apu_wr_reg(0x4000+c.chan*4,0xff);
+          rWrite(0x4000+c.chan*4,0xff);
         } else {
-          apu_wr_reg(0x4000+c.chan*4,0x30|chan[c.chan].vol|((chan[c.chan].duty&3)<<6));
+          rWrite(0x4000+c.chan*4,0x30|chan[c.chan].vol|((chan[c.chan].duty&3)<<6));
         }
       }
       break;
@@ -276,9 +278,16 @@ int DivPlatformNES::dispatch(DivCommand c) {
 
 void DivPlatformNES::muteChannel(int ch, bool mute) {
   isMuted[ch]=mute;
-  apu_wr_reg(0x4015,(!isMuted[0])|((!isMuted[1])<<1)|((!isMuted[2])<<2)|((!isMuted[3])<<3)|((!isMuted[4])<<4));
+  rWrite(0x4015,(!isMuted[0])|((!isMuted[1])<<1)|((!isMuted[2])<<2)|((!isMuted[3])<<3)|((!isMuted[4])<<4));
   if (isMuted[4]) {
-    apu_wr_reg(0x4011,0);
+    rWrite(0x4011,0);
+  }
+}
+
+void DivPlatformNES::forceIns() {
+  for (int i=0; i<5; i++) {
+    chan[i].insChanged=true;
+    chan[i].prevFreq=65535;
   }
 }
 
@@ -297,9 +306,9 @@ void DivPlatformNES::reset() {
   apu.cpu_cycles=0;
   apu.cpu_opcode_cycle=0;
 
-  apu_wr_reg(0x4015,(!isMuted[0])|((!isMuted[1])<<1)|((!isMuted[2])<<2)|((!isMuted[3])<<3)|((!isMuted[4])<<4));
-  apu_wr_reg(0x4001,0x08);
-  apu_wr_reg(0x4005,0x08);
+  rWrite(0x4015,(!isMuted[0])|((!isMuted[1])<<1)|((!isMuted[2])<<2)|((!isMuted[3])<<3)|((!isMuted[4])<<4));
+  rWrite(0x4001,0x08);
+  rWrite(0x4005,0x08);
 }
 
 bool DivPlatformNES::keyOffAffectsArp(int ch) {
diff --git a/src/engine/platform/nes.h b/src/engine/platform/nes.h
index 115f39371..6a6fd9778 100644
--- a/src/engine/platform/nes.h
+++ b/src/engine/platform/nes.h
@@ -41,11 +41,11 @@ class DivPlatformNES: public DivDispatch {
 
   float freqBase;
 
-  void updateWave();
   public:
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool keyOffAffectsArp(int ch);
diff --git a/src/engine/platform/pce.cpp b/src/engine/platform/pce.cpp
index 63916c037..e7c163436 100644
--- a/src/engine/platform/pce.cpp
+++ b/src/engine/platform/pce.cpp
@@ -3,13 +3,15 @@
 #include <math.h>
 
 //#define rWrite(a,v) pendingWrites[a]=v;
-#define rWrite(a,v) writes.emplace(a,v);
+#define rWrite(a,v) if (!skipRegisterWrites) {writes.emplace(a,v);}
 #define chWrite(c,a,v) \
-  if (curChan!=c) { \
-    curChan=c; \
-    rWrite(0,curChan); \
-  } \
-  rWrite(a,v);
+  if (!skipRegisterWrites) { \
+    if (curChan!=c) { \
+      curChan=c; \
+      rWrite(0,curChan); \
+    } \
+    rWrite(a,v); \
+  }
 
 #define FREQ_BASE 1712.0f*2
 
@@ -268,6 +270,13 @@ void DivPlatformPCE::muteChannel(int ch, bool mute) {
   chWrite(ch,0x05,isMuted[ch]?0:chan[ch].pan);
 }
 
+void DivPlatformPCE::forceIns() {
+  for (int i=0; i<6; i++) {
+    chan[i].insChanged=true;
+    updateWave(i);
+  }
+}
+
 void DivPlatformPCE::reset() {
   while (!writes.empty()) writes.pop();
   for (int i=0; i<6; i++) {
diff --git a/src/engine/platform/pce.h b/src/engine/platform/pce.h
index f96ae6983..5c0bb3520 100644
--- a/src/engine/platform/pce.h
+++ b/src/engine/platform/pce.h
@@ -57,6 +57,7 @@ class DivPlatformPCE: public DivDispatch {
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool isStereo();
diff --git a/src/engine/platform/ym2610.cpp b/src/engine/platform/ym2610.cpp
index 7167de51c..3d90383a8 100644
--- a/src/engine/platform/ym2610.cpp
+++ b/src/engine/platform/ym2610.cpp
@@ -104,14 +104,14 @@ void DivPlatformYM2610::tick() {
   for (int i=0; i<4; i++) {
     if (i==1 && extMode) continue;
     if (chan[i].keyOn || chan[i].keyOff) {
-      writes.emplace(0x28,0x00|konOffs[i]);
+      immWrite(0x28,0x00|konOffs[i]);
       chan[i].keyOff=false;
     }
   }
 
   for (int i=0; i<512; i++) {
     if (pendingWrites[i]!=oldWrites[i]) {
-      writes.emplace(i,pendingWrites[i]&0xff);
+      immWrite(i,pendingWrites[i]&0xff);
       oldWrites[i]=pendingWrites[i];
     }
   }
@@ -121,12 +121,12 @@ void DivPlatformYM2610::tick() {
     if (chan[i].freqChanged) {
       chan[i].freq=(chan[i].baseFreq*(ONE_SEMITONE+chan[i].pitch))/ONE_SEMITONE;
       int freqt=toFreq(chan[i].freq);
-      writes.emplace(chanOffs[i]+0xa4,freqt>>8);
-      writes.emplace(chanOffs[i]+0xa0,freqt&0xff);
+      immWrite(chanOffs[i]+0xa4,freqt>>8);
+      immWrite(chanOffs[i]+0xa0,freqt&0xff);
       chan[i].freqChanged=false;
     }
     if (chan[i].keyOn) {
-      writes.emplace(0x28,0xf0|konOffs[i]);
+      immWrite(0x28,0xf0|konOffs[i]);
       chan[i].keyOn=false;
     }
   }
@@ -177,22 +177,23 @@ int DivPlatformYM2610::dispatch(DivCommand c) {
   switch (c.cmd) {
     case DIV_CMD_NOTE_ON: {
       if (c.chan>6) { // ADPCM
+        if (skipRegisterWrites) break;
         if ((12*sampleBank+c.value%12)>=parent->song.sampleLen) {
-          writes.emplace(0x100,0x80|(1<<(c.chan-7)));
-          writes.emplace(0x110+c.chan-7,0);
-          writes.emplace(0x118+c.chan-7,0);
-          writes.emplace(0x120+c.chan-7,0);
-          writes.emplace(0x128+c.chan-7,0);
+          immWrite(0x100,0x80|(1<<(c.chan-7)));
+          immWrite(0x110+c.chan-7,0);
+          immWrite(0x118+c.chan-7,0);
+          immWrite(0x120+c.chan-7,0);
+          immWrite(0x128+c.chan-7,0);
           break;
         }
         DivSample* s=parent->song.sample[12*sampleBank+c.value%12];
-        writes.emplace(0x110+c.chan-7,(s->rendOff>>8)&0xff);
-        writes.emplace(0x118+c.chan-7,s->rendOff>>16);
+        immWrite(0x110+c.chan-7,(s->rendOff>>8)&0xff);
+        immWrite(0x118+c.chan-7,s->rendOff>>16);
         int end=s->rendOff+s->adpcmRendLength-1;
-        writes.emplace(0x120+c.chan-7,(end>>8)&0xff);
-        writes.emplace(0x128+c.chan-7,end>>16);
-        writes.emplace(0x108+(c.chan-7),isMuted[c.chan]?0:((chan[c.chan].pan<<6)|chan[c.chan].vol));
-        writes.emplace(0x100,0x00|(1<<(c.chan-7)));
+        immWrite(0x120+c.chan-7,(end>>8)&0xff);
+        immWrite(0x128+c.chan-7,end>>16);
+        immWrite(0x108+(c.chan-7),isMuted[c.chan]?0:((chan[c.chan].pan<<6)|chan[c.chan].vol));
+        immWrite(0x100,0x00|(1<<(c.chan-7)));
         break;
       }
       DivInstrument* ins=parent->getIns(chan[c.chan].ins);
@@ -247,7 +248,7 @@ int DivPlatformYM2610::dispatch(DivCommand c) {
     }
     case DIV_CMD_NOTE_OFF:
       if (c.chan>6) {
-        writes.emplace(0x100,0x80|(1<<(c.chan-7)));
+        immWrite(0x100,0x80|(1<<(c.chan-7)));
         break;
       }
       chan[c.chan].keyOff=true;
@@ -258,7 +259,7 @@ int DivPlatformYM2610::dispatch(DivCommand c) {
       chan[c.chan].vol=c.value;
       DivInstrument* ins=parent->getIns(chan[c.chan].ins);
       if (c.chan>6) { // ADPCM
-        writes.emplace(0x108+(c.chan-7),isMuted[c.chan]?0:((chan[c.chan].pan<<6)|chan[c.chan].vol));
+        immWrite(0x108+(c.chan-7),isMuted[c.chan]?0:((chan[c.chan].pan<<6)|chan[c.chan].vol));
         break;
       }
       if (c.chan>3) { // PSG
@@ -306,7 +307,7 @@ int DivPlatformYM2610::dispatch(DivCommand c) {
           break;
       }
       if (c.chan>6) {
-        writes.emplace(0x108+(c.chan-7),isMuted[c.chan]?0:((chan[c.chan].pan<<6)|chan[c.chan].vol));
+        immWrite(0x108+(c.chan-7),isMuted[c.chan]?0:((chan[c.chan].pan<<6)|chan[c.chan].vol));
         break;
       }
       if (c.chan>3) break;
@@ -434,7 +435,8 @@ int DivPlatformYM2610::dispatch(DivCommand c) {
       break;
     case DIV_CMD_AY_ENVELOPE_SET:
       if (c.chan<4 || c.chan>6) break;
-      rWrite(0x0d,c.value>>4);
+      ayEnvMode=c.value>>4;
+      rWrite(0x0d,ayEnvMode);
       if (c.value&15) {
         chan[c.chan].psgMode|=4;
       } else {
@@ -450,15 +452,15 @@ int DivPlatformYM2610::dispatch(DivCommand c) {
       if (c.chan<4 || c.chan>6) break;
       ayEnvPeriod&=0xff00;
       ayEnvPeriod|=c.value;
-      writes.emplace(0x0b,ayEnvPeriod);
-      writes.emplace(0x0c,ayEnvPeriod>>8);
+      immWrite(0x0b,ayEnvPeriod);
+      immWrite(0x0c,ayEnvPeriod>>8);
       break;
     case DIV_CMD_AY_ENVELOPE_HIGH:
       if (c.chan<4 || c.chan>6) break;
       ayEnvPeriod&=0xff;
       ayEnvPeriod|=c.value<<8;
-      writes.emplace(0x0b,ayEnvPeriod);
-      writes.emplace(0x0c,ayEnvPeriod>>8);
+      immWrite(0x0b,ayEnvPeriod);
+      immWrite(0x0c,ayEnvPeriod>>8);
       break;
     case DIV_ALWAYS_SET_VOLUME:
       return 0;
@@ -486,7 +488,7 @@ int DivPlatformYM2610::dispatch(DivCommand c) {
 void DivPlatformYM2610::muteChannel(int ch, bool mute) {
   isMuted[ch]=mute;
   if (ch>6) { // ADPCM
-    writes.emplace(0x108+(ch-7),isMuted[ch]?0:((chan[ch].pan<<6)|chan[ch].vol));
+    immWrite(0x108+(ch-7),isMuted[ch]?0:((chan[ch].pan<<6)|chan[ch].vol));
     return;
   }
   if (ch>3) { // PSG
@@ -502,6 +504,15 @@ void DivPlatformYM2610::muteChannel(int ch, bool mute) {
   rWrite(chanOffs[ch]+0xb4,(isMuted[ch]?0:(chan[ch].pan<<6))|(ins->fm.fms&7)|((ins->fm.ams&3)<<4));
 }
 
+void DivPlatformYM2610::forceIns() {
+  for (int i=0; i<13; i++) {
+    chan[i].insChanged=true;
+  }
+  immWrite(0x0b,ayEnvPeriod);
+  immWrite(0x0c,ayEnvPeriod>>8);
+  immWrite(0x0d,ayEnvMode);
+}
+
 void DivPlatformYM2610::reset() {
   while (!writes.empty()) writes.pop();
   fm->reset();
@@ -531,16 +542,17 @@ void DivPlatformYM2610::reset() {
   dacSample=-1;
   sampleBank=0;
   ayEnvPeriod=0;
+  ayEnvMode=0;
 
   delay=0;
 
   extMode=false;
 
   // LFO
-  writes.emplace(0x22,0x08);
+  immWrite(0x22,0x08);
 
   // PCM volume
-  writes.emplace(0x101,0x3f);
+  immWrite(0x101,0x3f);
 }
 
 bool DivPlatformYM2610::isStereo() {
diff --git a/src/engine/platform/ym2610.h b/src/engine/platform/ym2610.h
index 65199efaf..edcc38b35 100644
--- a/src/engine/platform/ym2610.h
+++ b/src/engine/platform/ym2610.h
@@ -54,6 +54,7 @@ class DivPlatformYM2610: public DivDispatch {
   
     short oldWrites[512];
     short pendingWrites[512];
+    unsigned char ayEnvMode;
     unsigned short ayEnvPeriod;
 
     int octave(int freq);
@@ -63,6 +64,7 @@ class DivPlatformYM2610: public DivDispatch {
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool isStereo();
diff --git a/src/engine/platform/ym2610ext.cpp b/src/engine/platform/ym2610ext.cpp
index b392e9507..3505c9789 100644
--- a/src/engine/platform/ym2610ext.cpp
+++ b/src/engine/platform/ym2610ext.cpp
@@ -207,7 +207,7 @@ void DivPlatformYM2610Ext::tick() {
       }
     }
     if (writeSomething) {
-      writes.emplace(0x28,writeMask);
+      immWrite(0x28,writeMask);
     }
   }
 
@@ -221,8 +221,8 @@ void DivPlatformYM2610Ext::tick() {
       int freqt=toFreq(opChan[i].freq);
       opChan[i].freqH=freqt>>8;
       opChan[i].freqL=freqt&0xff;
-      writes.emplace(opChanOffsH[i],opChan[i].freqH);
-      writes.emplace(opChanOffsL[i],opChan[i].freqL);
+      immWrite(opChanOffsH[i],opChan[i].freqH);
+      immWrite(opChanOffsL[i],opChan[i].freqL);
       opChan[i].freqChanged=false;
     }
     writeMask|=opChan[i].active<<(4+i);
@@ -233,7 +233,7 @@ void DivPlatformYM2610Ext::tick() {
     }
   }
   if (writeNoteOn) {
-    writes.emplace(0x28,writeMask);
+    immWrite(0x28,writeMask);
   }
 }
 
@@ -261,6 +261,13 @@ void DivPlatformYM2610Ext::muteChannel(int ch, bool mute) {
   }
 }
 
+void DivPlatformYM2610Ext::forceIns() {
+  DivPlatformYM2610::forceIns();
+  for (int i=0; i<4; i++) {
+    opChan[i].insChanged=true;
+  }
+}
+
 void DivPlatformYM2610Ext::reset() {
   DivPlatformYM2610::reset();
 
@@ -270,7 +277,7 @@ void DivPlatformYM2610Ext::reset() {
   }
 
   // channel 2 mode
-  writes.emplace(0x27,0x40);
+  immWrite(0x27,0x40);
   extMode=true;
 }
 
diff --git a/src/engine/platform/ym2610ext.h b/src/engine/platform/ym2610ext.h
index b2050a1df..46c085505 100644
--- a/src/engine/platform/ym2610ext.h
+++ b/src/engine/platform/ym2610ext.h
@@ -18,6 +18,7 @@ class DivPlatformYM2610Ext: public DivPlatformYM2610 {
   public:
     int dispatch(DivCommand c);
     void reset();
+    void forceIns();
     void tick();
     void muteChannel(int ch, bool mute);
     bool keyOffAffectsArp(int ch);
diff --git a/src/engine/platform/ym2610shared.h b/src/engine/platform/ym2610shared.h
index e02785248..79c16102c 100644
--- a/src/engine/platform/ym2610shared.h
+++ b/src/engine/platform/ym2610shared.h
@@ -23,7 +23,8 @@ static int orderedOps[4]={
   0,2,1,3
 };
 
-#define rWrite(a,v) pendingWrites[a]=v;
+#define rWrite(a,v) if (!skipRegisterWrites) {pendingWrites[a]=v;}
+#define immWrite(a,v) if (!skipRegisterWrites) {writes.emplace(a,v);}
 
 #define FM_FREQ_BASE 622.0f
 #define PSG_FREQ_BASE 7640.0f