This happened for hoshi on running a fresh nQuake install. He says Warsow worked fine on first run, so there has to be some client issue here.
[17:58] <hoshi> hoshi@hoshi-P35-DS4:~/nquake$ ./ezquake-gl.glx
[17:58] <hoshi> ALSA lib pcm.c:2212:(snd_pcm_open_noupdate) Unknown PCM /dev/dsp
[17:58] <hoshi> /dev/dsp: No such file or directory