Linux client use sdl as default sound wrapper.

Q: How can I specify what driver (oss...alsa) to use with these SDL games?
A: export SDL_AUDIODRIVER=dsp, other relevant options are:
    - alsa
    - artsc (Analog Realtime Synthesizer)
    - disk (goes to sdlaudio.raw in cwd)
    - dma (OSS /dev/dsp dma)
    - esd (Enlightenment Sound Daemon)
    - nas (Network Audio System)