> A few days ago, when i /did/ have a 5.1 amp with optical in, I heard what > could either have been only two front channels, or a mixdown. SPDIF is either 2 channels PCM, or data. Data can be AC3 or DTS compressed. To get this "data" mode, you need to tell mplayer NOT to decompress the audio! option: -afm hwac3 Adrian