> However when I run Linux or FreeBSD programs, such as RealAudio or Doom, that
> use /dev/dsp, all I get is this horrible random like noise coming out of my
> speaker.
Doom requires a 16 bit sound card if I remember right, and I think
RealAudio does too, unless you change some setting.

SoundBlaster with a DSP version < 4.0 does not support 16 bits.
Unfortunately, ES1688 does not emulate SB16.  I think ES1688 is
capable of 16 bit sound, but that requires a native driver for
it which we don't have right now.

        -- Lennart