Prank call show audio setup?

Most of you have heard of/watched Friday Night Cranks. I was wondering about their audio setup because I have a lot of friends on facefuck that would just love to watch it a few times a week and I already have a stickam and whatnot..

Here's how it's setup as simply as I can make it.

The audience to the pranks: can hear the caller, and the host, they do not hear any echoes, nor does anyone the person being called (ie if you say stereomix I'll cut your cock off).

The person being called: Can hear the host AND the music played on his computer if he chooses to play some.

The host: the ONLY person that can hear himself, he can hear the person he's calling too, obviously. So say he says hi to the person he can hear himself say it.


Now how in the fuck do I setup audio like this? Stickam has one input for sound, one input for cam, and one output for sound, nothing else so it has to be something he's doing on his computer.

 

bumpity