Bug#260757: rhythmbox: pausing and unpausing some songs introduces glitch in playback

[Jonathan Matthew]

Hi,

I'm seeing this too, with a wide variety of ogg vorbis and mp3 files,
with the ALSA emu10k1 and intel8x0 drivers from 2.6.7 kernel using osssink.
alsasink playback doesn't suffer from the same problem, but it does
suffer from problems similar to those reported in #262562.

It's much more noticeable with lower playback rate (44100hz vs 22050hz)
streams.  64kbit mp3s become completely unlistenable after
pause/unpause.  Normal bitrate streams (oggenc -q 3, or 128kbps mp3)
only suffer from mild distortion, barely noticeable most of the time. 

If the code to close the sound device on pause is removed (in
rb-player-gst.c, change 'if (may_pause == 1)' to 'if (0)' or comment out
that block), then pause/unpause does not affect sound quality.  I
suspect it's something to do with ALSA OSS emulation and how it deals
with the sequence of ioctls osssink issues when it opens the device, but 
that's just a hunch.

Also, this appears to have been reported to upstream bugzilla:
http://bugzilla.gnome.org/show_bug.cgi?id=148280
where the comments appear to indicate it doesn't happen with esdsink.

-jonathan.