[Lt Major Burns]

the TOS-link optical digital out on a G5 outputs up to 7.1 channels of discreet audio. get a compatible set of speakers (i use a sony amplified 5.1 set up) and link it with the TOS-Link fibre-optic cable. it only works some of the time, and awkwardly then, like it'll play all of the system sounds, but the volume controls in the system (including the keyboard ones) are disabled. if you are watching a dvd, you have to stop it and in the preferences, select digital optical, then play again. the true 5.1 channels are outputted, but there is still a small delay as the sound sorts itself out.

i find i am happier with just the quite-ample Pro-Logic II on the amp. it works well 99.% of the time.