I have the exact same problem. Same MB, same OS, same listings in modules.conf and with lspci.
I remember having the same problems with RH8, and finally got sound in the left channel - if I plugged the speaker-jack in the mic-plug, really weird. I also remeber struggeling with the ALSA driver and with the OSS driver, but without any results. I finally gave up and bought a new soundcard
I've been looking at, not tried, the ALSA drivers again, but they do not seem to have evolved since my last try.
I would also be very interested in any news or experiences, working or not, regarding this problem.
btw: I have got the module loaded, and the mixer is not muted.