The simple stuff first.
There are typically two stages to unmuting your card in alsamixer. The first is to use the M key to remove the mute. The second is to use the arrows to ensure your levels are up. You will want to bring up Master, Master Digital and PCM at a minimum.
Next thing is, see if you can play your sound with aplay. Sometimes oss emulation isn't working, but ALSA is working fine. That is a totally different problem, of course.
And take heart... There are lots of us with Aureal cards that work. The 2.6 Aureal drivers are problematic right now, but Aureal support in ALSA has been good for a while, and they're working hard to make it that way again!