pcm.dsp0 {
            type plug
            slave.pcm "dmix"
}
# or:
#  pcm.dsp0 pcm.default
# if "default" hasn't been redefined

ctl.mixer0 {
            type hw
            card 0
}

pcm.!default {
                type asym
                playback.pcm "dmix"
                capture.pcm "dsnoop"
}