Hi. I have one of these: http://www.m-audio.com/products/en_us/MobilePreUSB-main-1.html I also have a mic. Only problem is I can only go into one of the two channels, but I need to record the vocals in stereo. There's a little spot on the back that says "Stereo Mic Input" but the hole is small and doesn't fit anything that I have. Do you have any ideas?