Has anyone tried a multiple mic and headphone setup? Will be webcasting from a conference next week and may have more than two presenters at the computer that will be streaming. In the past I have manged 2 presenters with a shared USB mic and an RCA splitter for the headphones. So if anyone has any suggestions I'd be interested to hear. And just to make it more interesting - I'll be working on a Mac :-) (but would be interested to hear PC solutions too).