XBMC Frodo RC2 on Xubuntu 12.04 with external USB DAC, same problem here. My USB DAC is russian "Pegasus II" board, detected by ALSA (XBMC also) as USB PCM device and works great, until I put XBMC to sleep mode and then restore power.
In .xbmc/temp/xbmc.log this records appear many times per second
ERROR: CAESinkALSA::HandleError(snd_pcm_wait) - snd_pcm_writei returned -19 (No such device)
ERROR: CAESinkALSA::HandleError(snd_pcm_writei(1)) - snd_pcm_writei returned -19 (No such device)
ERROR: CAESinkALSA::HandleError(snd_pcm_writei(2)) - snd_pcm_writei returned -19 (No such device)
ERROR: CAESinkALSA::HandleError(snd_pcm_avail) - snd_pcm_writei returned -19 (No such device)
But device is still connected and working, seen by aplay -l and lspci.
IMHO, XBMC locks device, but forget to unlock it before to go to sleep mode, and when power restored, XBMC try to get lock on already locked device.
There is no such error in 11.0 Eden. No ALSA / kernel modules upgraded, just XBMC.
This problem can be solved in the way proposed in this thread, just create /etc/pm/sleep.d/80_xbmc-restart with following content
Code:
#! /bin/sh
case $1 in
resume|thaw)
/usr/bin/service lightdm restart
;;
esac
then chmod u+x /etc/pm/sleep.d/80_xbmc-restart
but this is not complete solution, just temporary one. Also, no need to restart ALSA completely because of XBMC will crash when alsa force-restart done.
Waiting for final release, Frodo is the best solution as standalone multimedia center + pvr for me.