[mythtv-users] AC3 passthrough is failing in certain circumstances

[Matt Redmon]

I have a few video files that have Dolby AC3 encoding.  When I try to play 
them with xine or gmplayer, they play back just fine in full 5.1 glory; 
however mplayer does not do likewise.  mplayer will either spit out the 
following message and exit or display the message and continue playing the 
clip with no sound:

ALSA lib setup.c:548:(add_elem) Cannot obtain info for CTL elem 
(MIXER,'IEC958 Playback AC97-SPSA',0,0,0): No such file or directory

I've tried many different variations of -ac hwac3, and -ao alsa:default but 
all seem to either cause mplayer to exit or to play w/o sound.  Now, the 
error message seems to indicate that there is no mixer control labeled 
IEC958....   and that is true.  The problem is that I cannot seem to find 
out why it is looking for that specific mixer.

I have a 7NIF2 and am using the onboard soundcard.  Absolutely everything 
else is working fine (2 channel and 5.1 surround on xine, 2 channel on 
mplayer; in recordings, videos, dvds, etc.).  I'm running 0.17 from ATRPMs 
on FC3.

Any ideas?

Thanks!

Matt