Pretty much the only thing that can go wrong with sound in darkplaces is if a sound card does not support mmapping a sound buffer, this is the case with many old oss sound drivers, and alsa before 0.9.
I can only offer these suggestions:
1. try different drivers (recent versions of alsa are what I personally recommend if they support your sound card).
2. wait for me to rewrite the sound system.
3. wait for me to port the sound system to SDL. (not easy, but at least Twilight has sample code so it won't be as hard as rewriting the sound system)
4. if I make the snd_alsa_0_9.c driver work again (haven't tested recently and doubt it's currently compilable) it may solve this problem for some people. (Making the snd_alsa_0_5.c driver work again might not be a bad idea either, but I'd prefer SDL as it doesn't require editing a makefile like this, it Just Works
I really hope this is helpful.
P.S. one other suggestion is that twilight probably works, it is here:
http://icculus.org/twilight
(SDL based and highly optimized, not many features though)
