I just got a new Logitech 2.1 audio system for my PowerBook (specs in sig). I first had them connected through the external speakers output on my PowerBook, but wasn't receiving any sound. I looked up help in Apple's help viewer and it said to connect them through the headphones jack instead. I did this and am receiving sound. It sounds great, but is this the way they're supposed to be connected? What is the other output for then? Thanks! And no, the speakers weren't showing up in the Output menu under the Sound pane.