Bug#455691: MP3 Decoding regression: audible clipping and popping

[Josh Triplett]

Package: gstreamer0.10-plugins-ugly
Version: 0.10.6-3
Severity: normal

Recently, I noticed that quodlibet started clipping some mp3s, with a
noticeable static pop.  Other players, such as mplayer or totem (using
totem-xine), play the same files fine with no clipping.  I tried
gst-launch with the mad decoder, and it had the same clipping.
gst-launch with "ffdemux_mp3 ! ffdec_mp3" as the decoder did not clip.
Finally, I tried using sox (which uses libmad) to convert the file
from mp3 to wav, which generated the message "sox sox: temp.wav:
output clipped 48802 samples; decrease volume?".  However, the resulting wav
did not clip in any player.

I tried to downgrade gstreamer to an older version to determine what
version introduced the regression, but the resulting gstreamer did not
want to play mp3s; mad would not hook up to alsasink, or to wavenc.

As a first guess, I've filed the bug against
gstreamer0.10-plugins-ugly; however, the problem may well lie
elsewhere.

Happy to run further tests to narrow down the problem.

- Josh Triplett