We have exactly the same problem and while looking through the status info for the emu10k1 driver we found this posting...
FROM: Takashi Iwai
DATE: 02/01/2002 11:19:44
SUBJECT: [Alsa-user] Audigy support status
now emu10k1 driver on cvs suports SB Audigy and seems working somehow
according to Steve Hassard:
- playback on front works. AC97 seems irrelevant and only
"Wave Playback Volume" affects actually.
- playback on rear - implemented - not work. no idea.
- playback on center/lfe - implemented - not tested
- digital (audio) outputs - implemented - not tested
- digital non-audio i/o - not implemented
no TRAM access yet
...does this mean that the rear speakers do not work at all at this stage, or am I reading this wrong?