diff --git a/src/engine/engine.h b/src/engine/engine.h
index 12fd05be0..9becc9d5f 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -18,7 +18,7 @@ struct DivChannelState {
   int vibratoDepth, vibratoRate, vibratoPos, vibratoDir, vibratoFine;
   int tremoloDepth, tremoloRate, tremoloPos;
   unsigned char arp, arpStage, arpTicks;
-  bool doNote, legato, portaStop;
+  bool doNote, legato, portaStop, keyOn;
 
   DivChannelState():
     note(-1),
@@ -40,7 +40,7 @@ struct DivChannelState {
     arp(0),
     arpStage(-1),
     arpTicks(1),
-    doNote(false), legato(false), portaStop(false) {}
+    doNote(false), legato(false), portaStop(false), keyOn(false) {}
 };
 
 class DivEngine {
diff --git a/src/engine/playback.cpp b/src/engine/playback.cpp
index 910e09169..6d220e3dd 100644
--- a/src/engine/playback.cpp
+++ b/src/engine/playback.cpp
@@ -163,6 +163,7 @@ void DivEngine::processRow(int i, bool afterDelay) {
   // note
   if (pat->data[curRow][0]==100) {
     chan[i].note=-1;
+    chan[i].keyOn=false;
     dispatchCmd(DivCommand(DIV_CMD_NOTE_OFF,i));
   } else if (!(pat->data[curRow][0]==0 && pat->data[curRow][1]==0)) {
     chan[i].note=pat->data[curRow][0]+pat->data[curRow][1]*12;
@@ -303,6 +304,13 @@ void DivEngine::processRow(int i, bool afterDelay) {
       dispatchCmd(DivCommand(DIV_CMD_NOTE_ON,i,chan[i].note,chan[i].volume>>8));
     }
     chan[i].doNote=false;
+    if (!chan[i].keyOn) {
+      if (chan[i].portaStop) {
+        chan[i].portaNote=-1;
+        chan[i].portaSpeed=-1;
+      }
+    }
+    chan[i].keyOn=true;
   }
 
   // post effects