Im using a Presonus FP10 plugged via firewire into a new MBP. When I use the headphone jack from the Presonus I can hear sound (by turning on monitoring within GarageBand). Is there anyway to use to laptop speakers instead of headphones? Or the laptop headphone jack instead of the one on the Presonus? If I wanted to use external speakers to monitor would I just plug them into the headphone jack on the Presonus? On the MBP? Ive tried plugging headphones into the laptop jack and got nothing. Also tried to listen back through the laptop speakers and got nothing. Only time I get sound is with headphones attached to the Presonus. Is there somewhere I need to go activate these other options?