Tail of the old song is remembered if the default sink is echo-cancelled
To reproduce:
- Configure echo cancellation (see the attached config, media-session.conf), make the echo-cancelled sink the default one.
- Find two music files. Verify with Audacity (or ffplay) that both start with at least a hundred milliseconds of near-silence as a lead-in.
- Use mpv (through your file manager's "open with" menu, if it is not the default player) to play the first music file.
- When it reaches the middle, pause mpv, wait a few seconds, then close it. Then wait another few seconds.
- Use mpv to play another music file.
Expected result: during step 5, only the sound from the second music file should be heard, with nothing before it.
Actual result: a few milliseconds of old audio (presumably still buffered somewhere in the echo canceller) are heard, then the lead-in silence from the second file, then the music.