diff --git a/src/engine/platform/tia.cpp b/src/engine/platform/tia.cpp
index 9bab0b4e..25d408ab 100644
--- a/src/engine/platform/tia.cpp
+++ b/src/engine/platform/tia.cpp
@@ -183,6 +183,11 @@ int DivPlatformTIA::dispatch(DivCommand c) {
       chan[c.chan].freqChanged=true;
       break;
     }
+    case DIV_CMD_WAVE:
+      chan[c.chan].shape=c.value&15;
+      rWrite(0x15+c.chan,chan[c.chan].shape);
+      chan[c.chan].freqChanged=true;
+      break;
     case DIV_ALWAYS_SET_VOLUME:
       return 0;
       break;
diff --git a/src/engine/playback.cpp b/src/engine/playback.cpp
index 47f1df38..91edd97b 100644
--- a/src/engine/playback.cpp
+++ b/src/engine/playback.cpp
@@ -374,6 +374,13 @@ bool DivEngine::perSystemPostEffect(int ch, unsigned char effect, unsigned char
           break;
       }
       break;
+    case DIV_SYSTEM_TIA:
+      switch (effect) {
+        case 0x10: // select waveform
+          dispatchCmd(DivCommand(DIV_CMD_WAVE,ch,effectVal));
+          break;
+      }
+      break;
     default:
       return false;
   }