Audio I/o Problem With Logic+g5, Ditched PC, but now in trouble - HELP! Options

[yingtong]

I've just taken the leap and dumped my trusty old 350 MHz PC and bought a lovely, shiny G5. Was a Cubase boy, but have decided that Logic would be best with a Mac - sadist for learning?

Anyhoo, my problem is - I can get audio out (via line out) from internal sounds (eg bleeps from changing the main volume on the G5 desktop), but no audio back out from the audio line in.

Audio MIDI Setup (AMS) looks fine - set to 44.1KHz, 16 Bit in and out - no mutes. In AMS the Input Volume, Device Mute and Play Thru are locked out? Is that normal?

I'm running Jaguar awaiting Panther. I have an Emagic MT4 + a Yamaha CS1x and Akai S2000 apparently working fine. In the Sound settings of System Preferences, the G5 is registering an input signal from my CS1x on the audio meter, but the audio doesn't come back out - even though those beeps come out when I change the main volume on the desktop.

Please friends, help me out with this. And please Apple, don't tell me your G5 built-in sound card isn't full duplex...

In hope,
yingtong