splitmuxsink: Avoid deadlock on release, harder
Unlock after broadcasting and wait for the pad to be free before relocking the muxer, giving the input probe a chance to react to our broadcast.
Improves the fix from !838 (merged).
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Unlock after broadcasting and wait for the pad to be free before relocking the muxer, giving the input probe a chance to react to our broadcast.
Improves the fix from !838 (merged).