This seems to have some similarities to what I previously reported on a completely different board and SoC (dove) in bug #528524
However, many of the symptoms are the exact opposite. Here are my observations so far on this bug:
Some sounds seem to play fine, while others are silent. For instance:
/usr/share/sounds/gnome/default/alerts/bark.ogg (48000 Hz):
with paplay: silence
with aplay: loud static
/usr/share/sounds/gnome/default/alerts/{drip,glass,sonar}.ogg (44100 Hz):
with paplay: plays correctly
with aplay: static
Other files I have tried hold true to this so far - 44100 Hz seems to be the only rate at which files play. Also I tried using speaker-test -t sine -r [rate] to generate 44100 Hz and 48000 Hz. The 48000 Hz was just silent, but at 44100 I could hear the tone.
ProblemType: Bug
Architecture: armel
Date: Mon Mar 8 20:34:04 2010
DistroRelease: Ubuntu 10.04
InstallationMedia: Ubuntu-Netbook 10.04 "Lucid Lynx" - Alpha armel+imx51 (20100303)
Package: libasound2 1.0.22-0ubuntu6
ProcEnviron:
LANG=en_US.utf8
SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-605.8-imx51
SourcePackage: alsa-lib
Uname: Linux 2.6.31-605-imx51 armv7l
attaching pulseverbose.log from running pulseaudio per instructions at wiki.ubuntu.