diff --git a/src/engine/platform/ay.cpp b/src/engine/platform/ay.cpp
index 83de1fa1..52ac6e57 100644
--- a/src/engine/platform/ay.cpp
+++ b/src/engine/platform/ay.cpp
@@ -593,6 +593,13 @@ void DivPlatformAY8910::poke(std::vector<DivRegWrite>& wlist) {
   for (DivRegWrite& i: wlist) immWrite(i.addr,i.val);
 }
 
+void DivPlatformAY8910::setExtClockDiv(unsigned int eclk, unsigned char ediv) {
+  if (extMode) {
+    extClock=eclk;
+    extDiv=ediv;
+  }
+}
+
 void DivPlatformAY8910::setFlags(unsigned int flags) {
   if (extMode) {
     chipClock=extClock;
diff --git a/src/engine/platform/ay.h b/src/engine/platform/ay.h
index a1f35d1b..f67a2ad9 100644
--- a/src/engine/platform/ay.h
+++ b/src/engine/platform/ay.h
@@ -91,6 +91,7 @@ class DivPlatformAY8910: public DivDispatch {
     friend void putDispatchChan(void*,int,int);
   
   public:
+    void setExtClockDiv(unsigned int eclk=COLOR_NTSC, unsigned char ediv=8);
     void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void* getChanState(int chan);
diff --git a/src/engine/platform/fmshared_OPM.h b/src/engine/platform/fmshared_OPM.h
index 97844656..9b838c19 100644
--- a/src/engine/platform/fmshared_OPM.h
+++ b/src/engine/platform/fmshared_OPM.h
@@ -26,16 +26,16 @@
 
 class DivPlatformOPM: public DivPlatformFMBase {
   protected:
-    const unsigned char ADDR_MULT_DT=0x40;
-    const unsigned char ADDR_TL=0x60;
-    const unsigned char ADDR_RS_AR=0x80;
-    const unsigned char ADDR_AM_DR=0xa0;
-    const unsigned char ADDR_DT2_D2R=0xc0;
-    const unsigned char ADDR_SL_RR=0xe0;
-    const unsigned char ADDR_NOTE=0x28;
-    const unsigned char ADDR_KF=0x30;
-    const unsigned char ADDR_FMS_AMS=0x38;
-    const unsigned char ADDR_LR_FB_ALG=0x20;
+    const unsigned short ADDR_MULT_DT=0x40;
+    const unsigned short ADDR_TL=0x60;
+    const unsigned short ADDR_RS_AR=0x80;
+    const unsigned short ADDR_AM_DR=0xa0;
+    const unsigned short ADDR_DT2_D2R=0xc0;
+    const unsigned short ADDR_SL_RR=0xe0;
+    const unsigned short ADDR_NOTE=0x28;
+    const unsigned short ADDR_KF=0x30;
+    const unsigned short ADDR_FMS_AMS=0x38;
+    const unsigned short ADDR_LR_FB_ALG=0x20;
 
     const unsigned short opOffs[4]={
       0x00, 0x08, 0x10, 0x18
diff --git a/src/engine/platform/fmshared_OPN.h b/src/engine/platform/fmshared_OPN.h
index 74e13219..0aaad16d 100644
--- a/src/engine/platform/fmshared_OPN.h
+++ b/src/engine/platform/fmshared_OPN.h
@@ -85,27 +85,27 @@
 
 class DivPlatformOPN: public DivPlatformFMBase {
   protected:
-    const unsigned char ADDR_MULT_DT=0x30;
-    const unsigned char ADDR_TL=0x40;
-    const unsigned char ADDR_RS_AR=0x50;
-    const unsigned char ADDR_AM_DR=0x60;
-    const unsigned char ADDR_DT2_D2R=0x70;
-    const unsigned char ADDR_SL_RR=0x80;
-    const unsigned char ADDR_SSG=0x90;
-    const unsigned char ADDR_FREQ=0xa0;
-    const unsigned char ADDR_FREQH=0xa4;
-    const unsigned char ADDR_FB_ALG=0xb0;
-    const unsigned char ADDR_LRAF=0xb4;
+    const unsigned short ADDR_MULT_DT=0x30;
+    const unsigned short ADDR_TL=0x40;
+    const unsigned short ADDR_RS_AR=0x50;
+    const unsigned short ADDR_AM_DR=0x60;
+    const unsigned short ADDR_DT2_D2R=0x70;
+    const unsigned short ADDR_SL_RR=0x80;
+    const unsigned short ADDR_SSG=0x90;
+    const unsigned short ADDR_FREQ=0xa0;
+    const unsigned short ADDR_FREQH=0xa4;
+    const unsigned short ADDR_FB_ALG=0xb0;
+    const unsigned short ADDR_LRAF=0xb4;
 
     const unsigned short opOffs[4]={
       0x00, 0x04, 0x08, 0x0c
     };
 
     double fmFreqBase;
-    double fmDivBase;
-    unsigned char ayDiv;
+    unsigned int fmDivBase;
+    unsigned int ayDiv;
 
-    DivPlatformOPN(double f=9440540.0, double d=72, unsigned char a=32):
+    DivPlatformOPN(double f=9440540.0, unsigned int d=72, unsigned int a=32):
       DivPlatformFMBase(),
       fmFreqBase(f),
       fmDivBase(d),
diff --git a/src/engine/platform/genesis.h b/src/engine/platform/genesis.h
index 7d2004f3..c46a992d 100644
--- a/src/engine/platform/genesis.h
+++ b/src/engine/platform/genesis.h
@@ -99,13 +99,6 @@ class DivPlatformGenesis: public DivPlatformOPN {
     Channel chan[10];
     DivDispatchOscBuffer* oscBuf[10];
     bool isMuted[10];
-    struct QueuedWrite {
-      unsigned short addr;
-      unsigned char val;
-      bool addrOrVal;
-      QueuedWrite(unsigned short a, unsigned char v): addr(a), val(v), addrOrVal(false) {}
-    };
-    std::deque<QueuedWrite> writes;
     ym3438_t fm;
 
     ymfm::ym2612* fm_ymfm;
diff --git a/src/engine/platform/sms.cpp b/src/engine/platform/sms.cpp
index 35bb9c40..71e9b0bc 100644
--- a/src/engine/platform/sms.cpp
+++ b/src/engine/platform/sms.cpp
@@ -35,7 +35,7 @@ const char* regCheatSheetGG[]={
 };
 
 const char** DivPlatformSMS::getRegisterSheet() {
-  return isStereo()?regCheatSheetGG:regCheatSheetSN;
+  return stereo?regCheatSheetGG:regCheatSheetSN;
 }
 
 const char* DivPlatformSMS::getEffectName(unsigned char effect) {
@@ -74,7 +74,7 @@ void DivPlatformSMS::acquire_nuked(short* bufL, short* bufR, size_t start, size_
     o=YMPSG_GetOutput(&sn_nuked);
     if (o<-32768) o=-32768;
     if (o>32767) o=32767;
-    bufL[h]=o;
+    bufL[h]=bufR[h]=o;
     for (int i=0; i<4; i++) {
       if (isMuted[i]) {
         oscBuf[i]->data[oscBuf[i]->needle++]=0;
@@ -86,13 +86,6 @@ void DivPlatformSMS::acquire_nuked(short* bufL, short* bufR, size_t start, size_
 }
 
 void DivPlatformSMS::acquire_mame(short* bufL, short* bufR, size_t start, size_t len) {
-  if (snBufLen<len) {
-    snBufLen=len;
-    for (int i=0; i<2; i++) {
-      delete[] snBuf[i];
-      snBuf[i]=new short[snBufLen];
-    }
-  }
   while (!writes.empty()) {
     QueuedWrite w=writes.front();
     if (stereo && (w.addr&1))
@@ -101,10 +94,10 @@ void DivPlatformSMS::acquire_mame(short* bufL, short* bufR, size_t start, size_t
       sn->write(w.val);
     writes.pop();
   }
-  for (size_t h=0; h<len; h++) {
+  for (size_t h=start; h<start+len; h++) {
     short* outs[2]={
-      &snBuf[0][h],
-      &snBuf[1][h],
+      &bufL[h],
+      &bufR[h]
     };
     sn->sound_stream_update(outs,1);
     for (int i=0; i<4; i++) {
@@ -115,17 +108,6 @@ void DivPlatformSMS::acquire_mame(short* bufL, short* bufR, size_t start, size_t
       }
     }
   }
-  if (stereo) {
-    for (size_t i=0; i<len; i++) {
-      bufL[i+start]=snBuf[0][i];
-      bufR[i+start]=snBuf[1][i];
-    }
-  } else {
-    for (size_t i=0; i<len; i++) {
-      bufL[i+start]=snBuf[0][i];
-      bufR[i+start]=bufL[i+start];
-    }
-  }
 }
 
 void DivPlatformSMS::acquire(short* bufL, short* bufR, size_t start, size_t len) {
@@ -138,7 +120,7 @@ void DivPlatformSMS::acquire(short* bufL, short* bufR, size_t start, size_t len)
 
 void DivPlatformSMS::tick(bool sysTick) {
   for (int i=0; i<4; i++) {
-    int CHIP_DIVIDER=64;
+    int CHIP_DIVIDER=toneDivider;
     if (i==3) CHIP_DIVIDER=noiseDivider;
     chan[i].std.next();
     if (chan[i].std.vol.had) {
@@ -185,10 +167,10 @@ void DivPlatformSMS::tick(bool sysTick) {
         }
       }
     }
-    if (isStereo()) {
+    if (stereo) {
       if (chan[i].std.panL.had) {
         lastPan&=~(0x11<<i);
-        lastPan|=((chan[i].std.panL.val&1)<<(i+4))|(((chan[i].std.panL.val>>1)&1)<<i);
+        lastPan|=((chan[i].std.panL.val&1)<<i)|(((chan[i].std.panL.val>>1)&1)<<(i+4));
         rWrite(1,lastPan);
       }
     }
@@ -204,7 +186,7 @@ void DivPlatformSMS::tick(bool sysTick) {
   }
   for (int i=0; i<3; i++) {
     if (chan[i].freqChanged) {
-      chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,true,0,chan[i].pitch2,chipClock,64);
+      chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,true,0,chan[i].pitch2,chipClock,toneDivider);
       if (chan[i].freq>1023) chan[i].freq=1023;
       if (chan[i].freq<8) chan[i].freq=1;
       //if (chan[i].actualNote>0x5d) chan[i].freq=0x01;
@@ -263,7 +245,7 @@ void DivPlatformSMS::tick(bool sysTick) {
 }
 
 int DivPlatformSMS::dispatch(DivCommand c) {
-  int CHIP_DIVIDER=64;
+  int CHIP_DIVIDER=toneDivider;
   if (c.chan==3) CHIP_DIVIDER=noiseDivider;
   switch (c.cmd) {
     case DIV_CMD_NOTE_ON:
@@ -340,11 +322,12 @@ int DivPlatformSMS::dispatch(DivCommand c) {
       updateSNMode=true;
       break;
     case DIV_CMD_PANNING: {
-      if (isStereo()) {
+      if (stereo) {
+        if (c.chan>3) c.chan=3;
         lastPan&=~(0x11<<c.chan);
         int pan=0;
-        if (c.value>0) pan|=0x01;
-        if (c.value2>0) pan|=0x10;
+        if (c.value>0) pan|=0x10;
+        if (c.value2>0) pan|=0x01;
         if (pan==0) pan=0x11;
         lastPan|=pan<<c.chan;
         rWrite(1,lastPan);
@@ -420,13 +403,13 @@ void DivPlatformSMS::reset() {
   updateSNMode=false;
   oldValue=0xff;
   lastPan=0xff;
-  if (isStereo()) {
+  if (stereo) {
     rWrite(1,0xff);
   }
 }
 
 bool DivPlatformSMS::isStereo() {
-  return (!nuked) && stereo;
+  return stereo;
 }
 
 bool DivPlatformSMS::keyOffAffectsArp(int ch) {
@@ -482,6 +465,7 @@ void DivPlatformSMS::setFlags(unsigned int flags) {
   }
   resetPhase=!(flags&16);
   divider=16;
+  toneDivider=64;
   noiseDivider=64;
   if (sn!=NULL) delete sn;
   switch (flags&0xcc) {
@@ -494,13 +478,11 @@ void DivPlatformSMS::setFlags(unsigned int flags) {
     case 0x04: // TI SN76489
       sn=new sn76489_device();
       isRealSN=true;
-      noiseDivider=60;
       stereo=false;
       break;
     case 0x08: // TI+Atari
       sn=new sn76496_base_device(0x4000, 0x0f35, 0x01, 0x02, true, false, 8, false, true);
       isRealSN=true;
-      noiseDivider=60;
       stereo=false;
       break;
     case 0x0c: // Game Gear (not fully emulated yet!)
@@ -511,40 +493,38 @@ void DivPlatformSMS::setFlags(unsigned int flags) {
     case 0x40: // TI SN76489A
       sn=new sn76489a_device();
       isRealSN=false; // TODO
-      noiseDivider=68;
       stereo=false;
       break;
     case 0x44: // TI SN76496
       sn=new sn76496_device();
       isRealSN=false; // TODO
-      noiseDivider=68;
       stereo=false;
       break;
     case 0x48: // NCR 8496
       sn=new ncr8496_device();
       isRealSN=false;
-      noiseDivider=64;
       stereo=false;
       break;
     case 0x4c: // Tandy PSSJ 3-voice sound
       sn=new pssj3_device();
       isRealSN=false;
-      noiseDivider=64;
       stereo=false;
       break;
     case 0x80: // TI SN94624
       sn=new sn94624_device();
       isRealSN=true;
-      noiseDivider=60;
       stereo=false;
       divider=2;
+      toneDivider=8;
+      noiseDivider=8;
       break;
     case 0x84: // TI SN76494
       sn=new sn76494_device();
       isRealSN=false; // TODO
-      noiseDivider=68;
       stereo=false;
       divider=2;
+      toneDivider=8;
+      noiseDivider=8;
       break;
   }
   rate=chipClock/divider;
@@ -570,8 +550,6 @@ int DivPlatformSMS::init(DivEngine* p, int channels, int sugRate, unsigned int f
   }
   sn=NULL;
   setFlags(flags);
-  snBufLen=65536;
-  for (int i=0; i<2; i++) snBuf[i]=new short[snBufLen];
   reset();
   return 4;
 }
@@ -580,9 +558,6 @@ void DivPlatformSMS::quit() {
   for (int i=0; i<4; i++) {
     delete oscBuf[i];
   }
-  for (int i=0; i<2; i++) {
-    delete[] snBuf[i];
-  }
   if (sn!=NULL) delete sn;
 }
 
diff --git a/src/engine/platform/sms.h b/src/engine/platform/sms.h
index 42399577..589bb9b8 100644
--- a/src/engine/platform/sms.h
+++ b/src/engine/platform/sms.h
@@ -59,11 +59,10 @@ class DivPlatformSMS: public DivDispatch {
   DivDispatchOscBuffer* oscBuf[4];
   bool isMuted[4];
   unsigned char lastPan;
-  short* snBuf[2];
-  size_t snBufLen;
   unsigned char oldValue; 
   unsigned char snNoiseMode;
   int divider=16;
+  int toneDivider=64;
   int noiseDivider=64;
   bool updateSNMode;
   bool resetPhase;
diff --git a/src/engine/platform/sound/sn76496.cpp b/src/engine/platform/sound/sn76496.cpp
index 4bbb5848..e76b403f 100644
--- a/src/engine/platform/sound/sn76496.cpp
+++ b/src/engine/platform/sound/sn76496.cpp
@@ -412,6 +412,6 @@ void sn76496_base_device::sound_stream_update(short** outputs, int outLen)
 
 		outputs[0][sampindex]=out;
 		if (m_stereo && (outputs[1] != nullptr))
-			outputs[1][sampindex]=out;
+			outputs[1][sampindex]=out2;
 	}
 }
diff --git a/src/engine/platform/ym2203.cpp b/src/engine/platform/ym2203.cpp
index a25c0e96..e0bbe1a3 100644
--- a/src/engine/platform/ym2203.cpp
+++ b/src/engine/platform/ym2203.cpp
@@ -981,6 +981,10 @@ void DivPlatformYM2203::reset() {
 
   extMode=false;
 
+  // set prescaler
+  immWrite(0x2d,0xff);
+  immWrite(prescale,0xff);
+
   ay->reset();
   ay->getRegisterWrites().clear();
   ay->flushWrites();
@@ -1013,7 +1017,8 @@ void DivPlatformYM2203::setSkipRegisterWrites(bool value) {
 }
 
 void DivPlatformYM2203::setFlags(unsigned int flags) {
-  switch (flags&0x3f) {
+  // Clock flags
+  switch (flags&0x1f) {
     default:
     case 0x00:
       chipClock=COLOR_NTSC;
@@ -1034,10 +1039,36 @@ void DivPlatformYM2203::setFlags(unsigned int flags) {
       chipClock=3000000.0/2.0;
       break;
   }
+  // Prescaler flags
+  switch ((flags>>5)&0x3) {
+    default:
+    case 0x00: // /6
+      prescale=0x2d;
+      fmFreqBase=4720270.0,
+      fmDivBase=36,
+      ayDiv=16;
+      break;
+    case 0x01: // /3
+      prescale=0x2e;
+      fmFreqBase=4720270.0/2.0,
+      fmDivBase=18,
+      ayDiv=8;
+      break;
+    case 0x02: // /2
+      prescale=0x2f;
+      fmFreqBase=4720270.0/3.0,
+      fmDivBase=12,
+      ayDiv=4;
+      break;
+  }
   rate=fm->sample_rate(chipClock);
   for (int i=0; i<6; i++) {
     oscBuf[i]->rate=rate;
   }
+  immWrite(0x2d,0xff);
+  immWrite(prescale,0xff);
+  ay->setExtClockDiv(chipClock,ayDiv);
+  ay->setFlags(16);
 }
 
 int DivPlatformYM2203::init(DivEngine* p, int channels, int sugRate, unsigned int flags) {
@@ -1050,11 +1081,11 @@ int DivPlatformYM2203::init(DivEngine* p, int channels, int sugRate, unsigned in
   }
   fm=new ymfm::ym2203(iface);
   fm->set_fidelity(ymfm::OPN_FIDELITY_MIN);
-  setFlags(flags);
   // YM2149, 2MHz
   ay=new DivPlatformAY8910(true,chipClock,ayDiv);
   ay->init(p,3,sugRate,16);
   ay->toggleRegisterDump(true);
+  setFlags(flags);
 
   reset();
   return 6;
diff --git a/src/engine/platform/ym2203.h b/src/engine/platform/ym2203.h
index 6d7bc420..d406e2f2 100644
--- a/src/engine/platform/ym2203.h
+++ b/src/engine/platform/ym2203.h
@@ -90,6 +90,7 @@ class DivPlatformYM2203: public DivPlatformOPN {
     unsigned char sampleBank;
 
     bool extMode;
+    unsigned char prescale;
   
     friend void putDispatchChan(void*,int,int);
   
@@ -118,7 +119,8 @@ class DivPlatformYM2203: public DivPlatformOPN {
     int init(DivEngine* parent, int channels, int sugRate, unsigned int flags);
     void quit();
     DivPlatformYM2203():
-      DivPlatformOPN(4720270.0, 36, 16) {}
+      DivPlatformOPN(4720270.0, 36, 16),
+      prescale(0x2d) {}
     ~DivPlatformYM2203();
 };
 #endif
diff --git a/src/engine/platform/ym2608.cpp b/src/engine/platform/ym2608.cpp
index 46b8b0ad..733f0481 100644
--- a/src/engine/platform/ym2608.cpp
+++ b/src/engine/platform/ym2608.cpp
@@ -1325,6 +1325,10 @@ void DivPlatformYM2608::reset() {
   // enable 6 channel mode
   immWrite(0x29,0x80);
 
+  // set prescaler
+  immWrite(0x2d,0xff);
+  immWrite(prescale,0xff);
+
   ay->reset();
   ay->getRegisterWrites().clear();
   ay->flushWrites();
@@ -1395,7 +1399,8 @@ void DivPlatformYM2608::renderSamples() {
 }
 
 void DivPlatformYM2608::setFlags(unsigned int flags) {
-  switch (flags&0x3f) {
+  // Clock flags
+  switch (flags&0x1f) {
     default:
     case 0x00:
       chipClock=8000000.0;
@@ -1404,10 +1409,36 @@ void DivPlatformYM2608::setFlags(unsigned int flags) {
       chipClock=38400*13*16; // 31948800/4
       break;
   }
+  // Prescaler flags
+  switch ((flags>>5)&0x3) {
+    default:
+    case 0x00: // /6
+      prescale=0x2d;
+      fmFreqBase=9440540.0,
+      fmDivBase=72,
+      ayDiv=32;
+      break;
+    case 0x01: // /3
+      prescale=0x2e;
+      fmFreqBase=9440540.0/2.0,
+      fmDivBase=36,
+      ayDiv=16;
+      break;
+    case 0x02: // /2
+      prescale=0x2f;
+      fmFreqBase=9440540.0/3.0,
+      fmDivBase=24,
+      ayDiv=8;
+      break;
+  }
   rate=fm->sample_rate(chipClock);
   for (int i=0; i<16; i++) {
     oscBuf[i]->rate=rate;
   }
+  immWrite(0x2d,0xff);
+  immWrite(prescale,0xff);
+  ay->setExtClockDiv(chipClock,ayDiv);
+  ay->setFlags(16);
 }
 
 int DivPlatformYM2608::init(DivEngine* p, int channels, int sugRate, unsigned int flags) {
@@ -1423,11 +1454,12 @@ int DivPlatformYM2608::init(DivEngine* p, int channels, int sugRate, unsigned in
     oscBuf[i]=new DivDispatchOscBuffer;
   }
   fm=new ymfm::ym2608(iface);
-  setFlags(flags);
+  fm->set_fidelity(ymfm::OPN_FIDELITY_MIN);
   // YM2149, 2MHz
-  ay=new DivPlatformAY8910(true,chipClock,32);
+  ay=new DivPlatformAY8910(true,chipClock,ayDiv);
   ay->init(p,3,sugRate,16);
   ay->toggleRegisterDump(true);
+  setFlags(flags);
   reset();
   return 16;
 }
diff --git a/src/engine/platform/ym2608.h b/src/engine/platform/ym2608.h
index c1f43f4d..ac38a8c0 100644
--- a/src/engine/platform/ym2608.h
+++ b/src/engine/platform/ym2608.h
@@ -101,8 +101,7 @@ class DivPlatformYM2608: public DivPlatformOPN {
     unsigned char writeRSSOff, writeRSSOn;
 
     bool extMode;
-    double fmFreqBase;
-    unsigned char ayDiv;
+    unsigned char prescale;
   
     double NOTE_OPNB(int ch, int note);
     double NOTE_ADPCMB(int note);
@@ -137,7 +136,8 @@ class DivPlatformYM2608: public DivPlatformOPN {
     int init(DivEngine* parent, int channels, int sugRate, unsigned int flags);
     void quit();
     DivPlatformYM2608():
-      DivPlatformOPN(9440540.0, 72, 32) {}
+      DivPlatformOPN(9440540.0, 72, 32),
+      prescale(0x2d) {}
     ~DivPlatformYM2608();
 };
 #endif
diff --git a/src/engine/song.h b/src/engine/song.h
index 6bbb00cf..df622d86 100644
--- a/src/engine/song.h
+++ b/src/engine/song.h
@@ -357,7 +357,7 @@ struct DivSong {
   //     - 3: 3MHz
   //     - 4: 3.9936MHz (PC-88, PC-98)
   //     - 5: 1.5MHz
-  //   - bit 5-6: output rate (TODO)
+  //   - bit 5-6: output rate
   //     - 0: FM: clock / 72, SSG: clock / 16
   //     - 1: FM: clock / 36, SSG: clock / 8
   //     - 2: FM: clock / 24, SSG: clock / 4
@@ -365,7 +365,7 @@ struct DivSong {
   //   - bit 0-4: clock rate
   //     - 0: 8MHz
   //     - 1: 7.987MHz (PC-88, PC-98)
-  //   - bit 5-6: output rate (TODO)
+  //   - bit 5-6: output rate
   //     - 0: FM: clock / 144, SSG: clock / 32
   //     - 1: FM: clock / 72, SSG: clock / 16
   //     - 2: FM: clock / 48, SSG: clock / 8
diff --git a/src/gui/presets.cpp b/src/gui/presets.cpp
index d0e63c11..5056de74 100644
--- a/src/gui/presets.cpp
+++ b/src/gui/presets.cpp
@@ -56,13 +56,13 @@ void FurnaceGUI::initSystemPresets() {
   ));
   cat.systems.push_back(FurnaceGUISysDef(
     "Yamaha YM2608 (OPNA)", {
-      DIV_SYSTEM_PC98, 64, 0, 3,
+      DIV_SYSTEM_PC98, 64, 0, 0,
       0
     }
   ));
   cat.systems.push_back(FurnaceGUISysDef(
     "Yamaha YM2608 (extended channel 3)", {
-      DIV_SYSTEM_PC98_EXT, 64, 0, 3,
+      DIV_SYSTEM_PC98_EXT, 64, 0, 0,
       0
     }
   ));
@@ -258,6 +258,18 @@ void FurnaceGUI::initSystemPresets() {
       0
     }
   ));
+  cat.systems.push_back(FurnaceGUISysDef(
+    "TI SN94624", {
+      DIV_SYSTEM_SMS, 64, 0, 0x80,
+      0
+    }
+  ));
+  cat.systems.push_back(FurnaceGUISysDef(
+    "TI SN76494", {
+      DIV_SYSTEM_SMS, 64, 0, 0x84,
+      0
+    }
+  ));
   cat.systems.push_back(FurnaceGUISysDef(
     "AY-3-8910", {
       DIV_SYSTEM_AY8910, 64, 0, 0,
diff --git a/src/gui/sysConf.cpp b/src/gui/sysConf.cpp
index 02d06db3..21fef35d 100644
--- a/src/gui/sysConf.cpp
+++ b/src/gui/sysConf.cpp
@@ -397,8 +397,7 @@ void FurnaceGUI::drawSysConf(int chan, DivSystem type, unsigned int& flags, bool
       if (ImGui::RadioButton("1.5MHz",(flags&31)==5)) {
         copyOfFlags=(flags&(~31))|5;
       }
-      /*
-      ImGui::Text("Output rate: (DOES NOT WORK YET!)");
+      ImGui::Text("Output rate:");
       if (ImGui::RadioButton("FM: clock / 72, SSG: clock / 16",(flags&96)==0)) {
         copyOfFlags=(flags&(~96))|0;
       }
@@ -408,7 +407,6 @@ void FurnaceGUI::drawSysConf(int chan, DivSystem type, unsigned int& flags, bool
       if (ImGui::RadioButton("FM: clock / 24, SSG: clock / 4",(flags&96)==64)) {
         copyOfFlags=(flags&(~96))|64;
       }
-      */
       break;
     }
     case DIV_SYSTEM_PC98:
@@ -420,8 +418,7 @@ void FurnaceGUI::drawSysConf(int chan, DivSystem type, unsigned int& flags, bool
       if (ImGui::RadioButton("7.987MHz (PC-88/PC-98)",(flags&31)==1)) {
         copyOfFlags=(flags&(~31))|1;
       }
-      /*
-      ImGui::Text("Output rate: (DOES NOT WORK YET!)");
+      ImGui::Text("Output rate:");
       if (ImGui::RadioButton("FM: clock / 144, SSG: clock / 32",(flags&96)==0)) {
         copyOfFlags=(flags&(~96))|0;
       }
@@ -431,7 +428,6 @@ void FurnaceGUI::drawSysConf(int chan, DivSystem type, unsigned int& flags, bool
       if (ImGui::RadioButton("FM: clock / 48, SSG: clock / 8",(flags&96)==64)) {
         copyOfFlags=(flags&(~96))|64;
       }
-      */
       break;
     }
     case DIV_SYSTEM_RF5C68: {