pipecat/changelog/4431.fixed.md

• Fixed a deadlock in TTSService that could permanently stall pipeline processing when all three conditions occurred together: pause_frame_processing=True, an interruption arrived before any TTS audio was played, and an UninterruptibleFrame (e.g. TTSUpdateSettingsFrame, FunctionCallResultFrame) was in the processing queue at that moment. The process task would block on __process_event.wait() indefinitely because BotStoppedSpeakingFrame never arrives (no audio was played) and the interruption handler did not resume processing. Affects services using pause_frame_processing=True such as ElevenLabs, Rime, AsyncAI, Gradium, and ResembleAI.