diff --git a/src/emucore/tia/Audio.cxx b/src/emucore/tia/Audio.cxx
index 7d35c9a89..49b3145f6 100644
--- a/src/emucore/tia/Audio.cxx
+++ b/src/emucore/tia/Audio.cxx
@@ -47,6 +47,9 @@ void Audio::reset()
 {
   myCounter = 0;
   mySampleIndex = 0;
+  sumChannel0 = 0;
+  sumChannel1 = 0;
+  sumCt = 0;
 
   myChannel0.reset();
   myChannel1.reset();
@@ -62,10 +65,15 @@ void Audio::setAudioQueue(const shared_ptr<AudioQueue>& queue)
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-void Audio::phase1()
+void Audio::createSample()
 {
-  const uInt8 sample0 = myChannel0.phase1();
-  const uInt8 sample1 = myChannel1.phase1();
+  // calculate average of all recent volume samples. the average for each
+  // channel is mixed to create a single audible value
+  const uInt8 sample0 = (uInt8)(sumChannel0/sumCt);
+  const uInt8 sample1 = (uInt8)(sumChannel1/sumCt);
+  sumChannel0 = 0;
+  sumChannel1 = 0;
+  sumCt = 0;
 
   addSample(sample0, sample1);
 #ifdef GUI_SUPPORT
diff --git a/src/emucore/tia/Audio.hxx b/src/emucore/tia/Audio.hxx
index 9a054c5b0..a18019b80 100644
--- a/src/emucore/tia/Audio.hxx
+++ b/src/emucore/tia/Audio.hxx
@@ -57,7 +57,7 @@ class Audio : public Serializable
     bool load(Serializer& in) override;
 
   private:
-    void phase1();
+    void createSample();
     void addSample(uInt8 sample0, uInt8 sample1);
 
   private:
@@ -68,6 +68,10 @@ class Audio : public Serializable
     AudioChannel myChannel0;
     AudioChannel myChannel1;
 
+	uInt32 sumChannel0;
+	uInt32 sumChannel1;
+	uInt32 sumCt;
+
     std::array<Int16, 0x1e + 1> myMixingTableSum;
     std::array<Int16, 0x0f + 1> myMixingTableIndividual;
 
@@ -92,6 +96,12 @@ class Audio : public Serializable
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void Audio::tick()
 {
+  // volume for each channel is sampled every color clock. the average of
+  // these samples will be taken twice a scanline in the phase1() function
+  sumChannel0 += (uInt32)myChannel0.actualVolume();
+  sumChannel1 += (uInt32)myChannel1.actualVolume();
+  sumCt++;
+
   switch (myCounter) {
     case 9:
     case 81:
@@ -101,7 +111,9 @@ void Audio::tick()
 
     case 37:
     case 149:
-      phase1();
+      myChannel0.phase1();
+      myChannel1.phase1();
+	  createSample();
       break;
 
     default:
diff --git a/src/emucore/tia/AudioChannel.cxx b/src/emucore/tia/AudioChannel.cxx
index 72db5a076..ad82fd801 100644
--- a/src/emucore/tia/AudioChannel.cxx
+++ b/src/emucore/tia/AudioChannel.cxx
@@ -77,7 +77,7 @@ void AudioChannel::phase0()
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-uInt8 AudioChannel::phase1()
+void AudioChannel::phase1()
 {
   if (myClockEnable) {
     bool pulseFeedback = false;
@@ -118,7 +118,12 @@ uInt8 AudioChannel::phase1()
       }
     }
   }
+}
 
+// the actual volume of a chaneel is the volume register multiplied by the
+// lowest of the pulse counter
+uInt8 AudioChannel::actualVolume() 
+{
   return (myPulseCounter & 0x01) * myAudv;
 }
 
diff --git a/src/emucore/tia/AudioChannel.hxx b/src/emucore/tia/AudioChannel.hxx
index 6302dcba3..ed62afafb 100644
--- a/src/emucore/tia/AudioChannel.hxx
+++ b/src/emucore/tia/AudioChannel.hxx
@@ -30,7 +30,9 @@ class AudioChannel : public Serializable
 
     void phase0();
 
-    uInt8 phase1();
+    void phase1();
+
+	uInt8 actualVolume();
 
     void audc(uInt8 value);