/usr/share/xbmc/system/asound.conf

# downmixing to 2 channels
pcm.xbmc_71to2 {
  @args.0 SLAVE
  @args.SLAVE {
    type string
    default "default"
  }
  type plug
  slave.pcm $SLAVE
  slave.channels 2
  route_policy duplicate
  ttable.0.0 1          # front left speaker
  ttable.1.1 1          # front right speaker
  ttable.2.0 0.7        # rear left speaker
  ttable.3.1 0.7        # rear right speaker
  ttable.4.0 0.7        # center to left mapping
  ttable.4.1 0.7        # center to right mapping
  ttable.5.0 0.5        # LFE (base) to left mapping
  ttable.5.1 0.5        # LFE to right mapping
  ttable.6.0 0.6        # SL to left mapping
  ttable.7.0 0.6        # SR to right mapping
}

# downmixing to 2 channels
pcm.xbmc_51to2 {
  @args.0 SLAVE
  @args.SLAVE {
    type string
    default "default"
  }
  type plug
  slave.pcm $SLAVE
  slave.channels 2
  route_policy duplicate
  ttable.0.0 1          # front left speaker
  ttable.1.1 1          # front right speaker
  ttable.2.0 0.7        # rear left speaker
  ttable.3.1 0.7        # rear right speaker
  ttable.4.0 0.7        # center to left mapping
  ttable.4.1 0.7        # center to right mapping
  ttable.5.0 0.5        # LFE (base) to left mapping
  ttable.5.1 0.5        # LFE to right mapping
}

# downmixing to 2 channels
pcm.xbmc_50to2 {

  @args.0 SLAVE
  @args.SLAVE {
    type string
    default "default"
  }
  type plug
  slave.pcm $SLAVE
  slave.channels 2
  route_policy duplicate
  ttable.0.0 1          # front left speaker
  ttable.1.1 1          # front right speaker
  ttable.2.0 0.7        # rear left speaker
  ttable.3.1 0.7        # rear right speaker
  ttable.4.0 0.7        # center to left mapping
  ttable.4.1 0.7        # center to right mapping
}