Hello all, I recently got a macbook air and I have logitech z 5500 from when I had my last pc. I bought a mini toslink - toslink cable and have it plugged in the optical output to my logitech control center. however, no sound... I have tried getting Perian and following some steps I was reading about Audio MIDI setup, but there is no option to select anything for "source" except for "headphones"... how can I get these speakers to work on my macbook air? Thanks!