The receiver buffers PCM per speaker with no conversation identity, and a same-voice-channel /voice join keeps that receiver. The poll and the leave flush then read the binding after draining, so audio captured for channel A was stamped with B and passed the post-STT check. The gateway join handler now discards the receiver's unemitted audio, under its lock, before moving the binding to a different text channel; a first join or same-channel rejoin keeps it. Nothing awaits between the discard and the binding write.
Reported by andrexibiza (F1) on #133471 and #130312.
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