diff --git a/src/engine/dispatch.h b/src/engine/dispatch.h
index 127ffc18c..abfe370a7 100644
--- a/src/engine/dispatch.h
+++ b/src/engine/dispatch.h
@@ -85,10 +85,12 @@ class DivDispatch {
      * the engine shall resample to the output rate.
      */
     int rate;
-    virtual void acquire(short** buf, size_t start, size_t len);
+    virtual void acquire(short* bufL, short* bufR, size_t start, size_t len);
     virtual int dispatch(DivCommand c);
     virtual void tick();
 
+    virtual bool isStereo();
+
     /**
      * initialize this DivDispatch.
      * @param parent the parent DivEngine.
diff --git a/src/engine/platform/abstract.cpp b/src/engine/platform/abstract.cpp
index 52a100756..4086edb00 100644
--- a/src/engine/platform/abstract.cpp
+++ b/src/engine/platform/abstract.cpp
@@ -1,6 +1,6 @@
 #include "../dispatch.h"
 
-void DivDispatch::acquire(short** buf, size_t start, size_t len) {
+void DivDispatch::acquire(short* bufL, short* bufR, size_t start, size_t len) {
 }
 
 void DivDispatch::tick() {
@@ -10,6 +10,10 @@ int DivDispatch::dispatch(DivCommand c) {
   return 1;
 }
 
+bool DivDispatch::isStereo() {
+  return false;
+}
+
 int DivDispatch::init(DivEngine* p, int channels, int sugRate) {
   return 0;
 }
diff --git a/src/engine/platform/c64.cpp b/src/engine/platform/c64.cpp
index 11fb8cb63..b7c4e9dbc 100644
--- a/src/engine/platform/c64.cpp
+++ b/src/engine/platform/c64.cpp
@@ -4,11 +4,10 @@
 
 #define FREQ_BASE 277.0f
 
-void DivPlatformC64::acquire(short** buf, size_t start, size_t len) {
+void DivPlatformC64::acquire(short* bufL, short* bufR, size_t start, size_t len) {
   for (size_t i=start; i<start+len; i++) {
     sid.clock();
-    buf[0][i]=sid.output();
-    buf[1][i]=buf[0][i];
+    bufL[i]=sid.output();
   }
 }
 
diff --git a/src/engine/platform/c64.h b/src/engine/platform/c64.h
index a7b45fe9f..39b2aeb30 100644
--- a/src/engine/platform/c64.h
+++ b/src/engine/platform/c64.h
@@ -39,7 +39,7 @@ class DivPlatformC64: public DivDispatch {
 
   void updateWave();
   public:
-    void acquire(short** buf, size_t start, size_t len);
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void tick();
     int init(DivEngine* parent, int channels, int sugRate);
diff --git a/src/engine/platform/dummy.cpp b/src/engine/platform/dummy.cpp
index 972ed659b..9e161b9a5 100644
--- a/src/engine/platform/dummy.cpp
+++ b/src/engine/platform/dummy.cpp
@@ -2,16 +2,15 @@
 #include <stdio.h>
 #include <math.h>
 
-void DivPlatformDummy::acquire(short** buf, size_t start, size_t len) {
+void DivPlatformDummy::acquire(short* bufL, short* bufR, size_t start, size_t len) {
   for (size_t i=start; i<start+len; i++) {
-    buf[0][i]=0;
+    bufL[i]=0;
     for (unsigned char j=0; j<chans; j++) {
       if (chan[j].active) {
-        buf[0][i]+=((chan[j].pos>=0x8000)?chan[j].vol:-chan[j].vol)*chan[j].amp;
+        bufL[i]+=((chan[j].pos>=0x8000)?chan[j].vol:-chan[j].vol)*chan[j].amp;
         chan[j].pos+=chan[j].freq;
       }
     }
-    buf[1][i]=buf[0][i];
   }
 }
 
diff --git a/src/engine/platform/dummy.h b/src/engine/platform/dummy.h
index f220e35a5..626a502d7 100644
--- a/src/engine/platform/dummy.h
+++ b/src/engine/platform/dummy.h
@@ -15,7 +15,7 @@ class DivPlatformDummy: public DivDispatch {
   Channel chan[17];
   unsigned char chans;
   public:
-    void acquire(short** buf, size_t start, size_t len);
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void tick();
     int init(DivEngine* parent, int channels, int sugRate);
diff --git a/src/engine/platform/gb.cpp b/src/engine/platform/gb.cpp
index 90385cd24..331e31cbe 100644
--- a/src/engine/platform/gb.cpp
+++ b/src/engine/platform/gb.cpp
@@ -7,11 +7,11 @@
 
 #define FREQ_BASE 8015.85f
 
-void DivPlatformGB::acquire(short** buf, size_t start, size_t len) {
+void DivPlatformGB::acquire(short* bufL, short* bufR, size_t start, size_t len) {
   for (int i=start; i<start+len; i++) {
     GB_advance_cycles(gb,16);
-    buf[0][i]=gb->apu_output.final_sample.left<<2;
-    buf[1][i]=gb->apu_output.final_sample.right<<2;
+    bufL[i]=gb->apu_output.final_sample.left<<2;
+    bufR[i]=gb->apu_output.final_sample.right<<2;
   }
 }
 
@@ -270,6 +270,10 @@ int DivPlatformGB::dispatch(DivCommand c) {
   return 1;
 }
 
+bool DivPlatformGB::isStereo() {
+  return true;
+}
+
 int DivPlatformGB::init(DivEngine* p, int channels, int sugRate) {
   parent=p;
   rate=262144;
diff --git a/src/engine/platform/gb.h b/src/engine/platform/gb.h
index 19e4f519d..aab8fe481 100644
--- a/src/engine/platform/gb.h
+++ b/src/engine/platform/gb.h
@@ -36,9 +36,10 @@ class DivPlatformGB: public DivDispatch {
   GB_gameboy_t* gb;
   void updateWave();
   public:
-    void acquire(short** buf, size_t start, size_t len);
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void tick();
+    bool isStereo();
     int init(DivEngine* parent, int channels, int sugRate);
 };
 
diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 6aa1b0862..5321303c6 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -12,7 +12,7 @@ static unsigned char konOffs[6]={
   0, 1, 2, 4, 5, 6
 };
 
-void DivPlatformGenesis::acquire(short** buf, size_t start, size_t len) {
+void DivPlatformGenesis::acquire(short* bufL, short* bufR, size_t start, size_t len) {
   static short o[2];
   static int os[2];
 
@@ -63,8 +63,8 @@ void DivPlatformGenesis::acquire(short** buf, size_t start, size_t len) {
       psgClocks-=rate;
     }
   
-    buf[0][h]=(os[0]<<5)+psgOut;
-    buf[1][h]=(os[1]<<5)+psgOut;
+    bufL[h]=(os[0]<<5)+psgOut;
+    bufR[h]=(os[1]<<5)+psgOut;
   }
 }
 
@@ -340,6 +340,10 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
   return 1;
 }
 
+bool DivPlatformGenesis::isStereo() {
+  return true;
+}
+
 int DivPlatformGenesis::init(DivEngine* p, int channels, int sugRate) {
   parent=p;
   rate=213068;
diff --git a/src/engine/platform/genesis.h b/src/engine/platform/genesis.h
index 522c002fb..c4292d47a 100644
--- a/src/engine/platform/genesis.h
+++ b/src/engine/platform/genesis.h
@@ -48,9 +48,10 @@ class DivPlatformGenesis: public DivDispatch {
     int toFreq(int freq);
   
   public:
-    void acquire(short** buf, size_t start, size_t len);
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void tick();
+    bool isStereo();
     int init(DivEngine* parent, int channels, int sugRate);
 };
 #endif
diff --git a/src/engine/platform/nes.cpp b/src/engine/platform/nes.cpp
index 185d48ae0..1a256fe4e 100644
--- a/src/engine/platform/nes.cpp
+++ b/src/engine/platform/nes.cpp
@@ -5,7 +5,7 @@
 
 #define FREQ_BASE 3424.0f
 
-void DivPlatformNES::acquire(short** buf, size_t start, size_t len) {
+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) {
       dacPeriod+=dacRate;
@@ -27,10 +27,8 @@ void DivPlatformNES::acquire(short** buf, size_t start, size_t len) {
     apu.odd_cycle=!apu.odd_cycle;
     if (apu.clocked) {
       apu.clocked=false;
-      buf[0][i]=(pulse_output()+tnd_output())*30;
-      buf[1][i]=buf[0][i];
-      //printf("output value: %d\n",l);
     }
+    bufL[i]=(pulse_output()+tnd_output())*30;
   }
 }
 
diff --git a/src/engine/platform/nes.h b/src/engine/platform/nes.h
index 2e1859ac4..db4a0ef68 100644
--- a/src/engine/platform/nes.h
+++ b/src/engine/platform/nes.h
@@ -36,7 +36,7 @@ class DivPlatformNES: public DivDispatch {
 
   void updateWave();
   public:
-    void acquire(short** buf, size_t start, size_t len);
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void tick();
     int init(DivEngine* parent, int channels, int sugRate);
diff --git a/src/engine/platform/pce.cpp b/src/engine/platform/pce.cpp
index ff6f7c602..883e41a48 100644
--- a/src/engine/platform/pce.cpp
+++ b/src/engine/platform/pce.cpp
@@ -13,7 +13,7 @@
 
 #define FREQ_BASE 1712.0f*2
 
-void DivPlatformPCE::acquire(short** buf, size_t start, size_t len) {
+void DivPlatformPCE::acquire(short* bufL, short* bufR, size_t start, size_t len) {
   for (size_t h=start; h<start+len; h++) {
     // PCM part
     for (int i=0; i<6; i++) {
@@ -47,8 +47,8 @@ void DivPlatformPCE::acquire(short** buf, size_t start, size_t len) {
     pce->ResetTS(0);
     
     //printf("tempL: %d tempR: %d\n",tempL,tempR);
-    buf[0][h]=tempL;
-    buf[1][h]=tempR;
+    bufL[h]=tempL;
+    bufR[h]=tempR;
   }
 }
 
@@ -250,6 +250,10 @@ int DivPlatformPCE::dispatch(DivCommand c) {
   return 1;
 }
 
+bool DivPlatformPCE::isStereo() {
+  return true;
+}
+
 int DivPlatformPCE::init(DivEngine* p, int channels, int sugRate) {
   parent=p;
   rate=1789773;
diff --git a/src/engine/platform/pce.h b/src/engine/platform/pce.h
index 2775dc0bb..8ed9d8a7a 100644
--- a/src/engine/platform/pce.h
+++ b/src/engine/platform/pce.h
@@ -50,9 +50,10 @@ class DivPlatformPCE: public DivDispatch {
   PCE_PSG* pce;
   void updateWave(int ch);
   public:
-    void acquire(short** buf, size_t start, size_t len);
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void tick();
+    bool isStereo();
     int init(DivEngine* parent, int channels, int sugRate);
 };
 
diff --git a/src/engine/platform/sms.cpp b/src/engine/platform/sms.cpp
index 99cc2a89f..6abbbc20c 100644
--- a/src/engine/platform/sms.cpp
+++ b/src/engine/platform/sms.cpp
@@ -2,9 +2,8 @@
 #include "../engine.h"
 #include <math.h>
 
-void DivPlatformSMS::acquire(short** buf, size_t start, size_t len) {
-  sn->sound_stream_update(buf[0]+start,len);
-  memcpy(buf[1]+start,buf[0]+start,sizeof(short)*len);
+void DivPlatformSMS::acquire(short* bufL, short* bufR, size_t start, size_t len) {
+  sn->sound_stream_update(bufL+start,len);
 }
 
 int DivPlatformSMS::acquireOne() {
diff --git a/src/engine/platform/sms.h b/src/engine/platform/sms.h
index a390ca909..33d4a9c40 100644
--- a/src/engine/platform/sms.h
+++ b/src/engine/platform/sms.h
@@ -31,7 +31,7 @@ class DivPlatformSMS: public DivDispatch {
   sn76496_device* sn;
   public:
     int acquireOne();
-    void acquire(short** buf, size_t start, size_t len);
+    void acquire(short* bufL, short* bufR, size_t start, size_t len);
     int dispatch(DivCommand c);
     void tick();
     int init(DivEngine* parent, int channels, int sugRate);
diff --git a/src/engine/playback.cpp b/src/engine/playback.cpp
index d98339b13..a60320cf7 100644
--- a/src/engine/playback.cpp
+++ b/src/engine/playback.cpp
@@ -618,11 +618,11 @@ void DivEngine::nextBuf(float** in, float** out, int inChans, int outChans, unsi
   while (runLeft) {
     if (runLeft>=cycles) {
       runLeft-=cycles;
-      dispatch->acquire(bbIn,runPos,cycles);
+      dispatch->acquire(bbIn[0],bbIn[1],runPos,cycles);
       runPos+=cycles;
       nextTick();
     } else {
-      dispatch->acquire(bbIn,runPos,runLeft);
+      dispatch->acquire(bbIn[0],bbIn[1],runPos,runLeft);
       cycles-=runLeft;
       break;
     }
@@ -634,20 +634,29 @@ void DivEngine::nextBuf(float** in, float** out, int inChans, int outChans, unsi
     prevSample[0]=temp[0];
   }
 
-  for (size_t i=0; i<runtotal; i++) {
+  if (dispatch->isStereo()) for (size_t i=0; i<runtotal; i++) {
     temp[1]=bbIn[1][i];
     blip_add_delta(bb[1],i,temp[1]-prevSample[1]);
     prevSample[1]=temp[1];
   }
 
   blip_end_frame(bb[0],runtotal);
-  blip_end_frame(bb[1],runtotal);
-
   blip_read_samples(bb[0],bbOut[0],size,0);
-  blip_read_samples(bb[1],bbOut[1],size,0);
 
-  for (size_t i=0; i<size; i++) {
-    out[0][i]=(float)bbOut[0][i]/16384.0;
-    out[1][i]=(float)bbOut[1][i]/16384.0;
+  if (dispatch->isStereo()) {
+    blip_end_frame(bb[1],runtotal);
+    blip_read_samples(bb[1],bbOut[1],size,0);
+  }
+
+  if (dispatch->isStereo()) {
+    for (size_t i=0; i<size; i++) {
+      out[0][i]=(float)bbOut[0][i]/16384.0;
+      out[1][i]=(float)bbOut[1][i]/16384.0;
+    }
+  } else {
+    for (size_t i=0; i<size; i++) {
+      out[0][i]=(float)bbOut[0][i]/16384.0;
+      out[1][i]=(float)bbOut[0][i]/16384.0;
+    }
   }
 }