"the right combination of encryption, network name and password."
[giggle] yes, that would help, and isn't exactly a Linux-specific issue!

What sort of sound card is it?
There's a huge list of soundcard support info on the ALSA project soundcard matrix (I assume your system uses ALSA, not OSS for sound) so worth checking there.
Can you run alsaconf from a command line? (probably need to say sudo alsaconf)
Does it recognise any sound hardware when you do that?

Anahata