docs: add CHANGELOG entry for skip_tts bug fix

Only set skip_tts=True when _skip_tts is configured, rather than
unconditionally overwriting the frame's skip_tts value. This preserves
frames that already have skip_tts=True when passing through LLM services.

Fixes issue where LLMTextFrame with skip_tts=True would exit LLMSwitcher
with skip_tts=False.

CHANGELOG.md

@@ -279,6 +279,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Fixed an issue where `LLMTextFrame` with `skip_tts=True` would have its value
+  overwritten to `False` when passing through LLM services (e.g., `LLMSwitcher`).
+  The fix preserves frames that already have `skip_tts=True` set.
+
 - Fixed an issue in `AWSBedrockLLMService` where the `aws_region` arg was
   always set to `us-east-1`.
 

src/pipecat/services/llm_service.py

@@ -292,8 +292,11 @@ class LLMService(AIService):
             frame: The frame to push.
             direction: The direction of frame pushing.
         """
+        # Only set skip_tts=True when configured, to preserve frames that already
+        # have skip_tts=True. This avoids overwriting frames passing through.
         if isinstance(frame, (LLMTextFrame, LLMFullResponseStartFrame, LLMFullResponseEndFrame)):
-            frame.skip_tts = self._skip_tts
+            if self._skip_tts:
+                frame.skip_tts = True
 
         await super().push_frame(frame, direction)