diff --git a/program/MapWindow.cs b/program/MapWindow.cs
index 473e821..d742f3f 100644
--- a/program/MapWindow.cs
+++ b/program/MapWindow.cs
@@ -188,6 +188,7 @@
     private bool _audible;                                  // true while a tag has the sound unmuted
     private uint _waveTimerId;
     private readonly System.Diagnostics.Stopwatch _playClock = new System.Diagnostics.Stopwatch();
+    private bool _heartLive, _breathLive;   // is this box's sound actually playing?
 
     // ══════════════════════════════════════════════════════════════════
 
@@ -1627,19 +1628,23 @@
 
     private void LoadWaveforms(CaseDefinition def)
     {
-        _heartWave = _breathWave = null;
         _heartCursor = _breathCursor = -1;
 
         WaveData caseWave = LoadWave(def.SoundPath);
+
         if (def.IsHeart)
         {
-            _heartWave = caseWave;
-            if (BreathSoundEnabled) _breathWave = LoadWave("sound/SND200.wav");
+            _heartWave  = caseWave;
+            _breathWave = LoadWave("sound/SND200.wav");   // default breath sound
+            _heartLive  = true;
+            _breathLive = BreathSoundEnabled;             // only "playing" if that voice was warmed
         }
         else
         {
             _breathWave = caseWave;
-            if (HeartSoundEnabled) _heartWave = LoadWave("sound/SND100.wav");
+            _heartWave  = LoadWave("sound/SND100.wav");   // default heart sound
+            _breathLive = true;
+            _heartLive  = HeartSoundEnabled;
         }
 
         HeartWaveArea.QueueDraw();
@@ -1698,8 +1703,8 @@
         }
 
         double t = _playClock.Elapsed.TotalSeconds;
-        _heartCursor  = CursorFor(_heartWave,  t);
-        _breathCursor = CursorFor(_breathWave, t);
+        _heartCursor  = _heartLive  ? CursorFor(_heartWave,  t) : -1;
+        _breathCursor = _breathLive ? CursorFor(_breathWave, t) : -1;
 
         HeartWaveArea.QueueDraw();
         BreathWaveArea.QueueDraw();