I always encode audio streams in MP3 and I always had great results.. maybe try to use 192Kbit/sec instead of 128Kbit/sec with MP3 audio, but quality is really great! I've never tried with multi speakers systems, but I think that the quality/size ratio is really better with MP3s.. A friend on mine also pointed me to ogg encoding, but I never had time to try that :roll:
Take a look at
www.doom9.com that sita has a great guide section and the forum is full of expert users
