Playing audio during a Podcast.
I'm starting a Podcast with Garageband. I have 3 USB mics hooked up and they all record separate people. So I have that figured out. Now what I want to do is play audio clips (news stories, YouTube, etc.) while we are recording the show so we can comment. I would like to do this from the computer I use to record the podcast. I need the audio clips I'm playing to be picked up by Garageband while the podcast it recording. I've tried changing my output sound to the USB mics but that didn't really seem to work. Thoughts?
GarageBand (Mac) '11, Mac OS X (10.7.3)