diff --git a/changelog/2955.fixed.md b/changelog/2955.fixed.md
new file mode 100644
index 000000000..431eafc44
--- /dev/null
+++ b/changelog/2955.fixed.md
@@ -0,0 +1 @@
+- Fixed audio mixer not being stopped on pipeline cancellation, causing 100% CPU usage after call disconnect.
diff --git a/src/pipecat/transports/base_output.py b/src/pipecat/transports/base_output.py
index 15eb99f3a..1471e06b3 100644
--- a/src/pipecat/transports/base_output.py
+++ b/src/pipecat/transports/base_output.py
@@ -504,6 +504,10 @@ class BaseOutputTransport(FrameProcessor):
             await self._cancel_clock_task()
             await self._cancel_video_task()
 
+            # Stop audio mixer so it doesn't keep generating frames after cancellation.
+            if self._mixer:
+                await self._mixer.stop()
+
         async def handle_interruptions(self, _: InterruptionFrame):
             """Handle interruption events by restarting tasks and clearing buffers.