How can I take a 4 channel USB audio input device and get it to work with software that just sees 2 channels of input? Let me explain better. I have a Focusrite Scarlett 18i8 (providing 4 tracks to the Mac through a USB), with 4 SHURE SM93 mics, feeding into a Mac and want to record them on Mac TechSmith Camtasia or use with Google Hangouts On-air. From what I understand is Camtasia and Google Hangouts on-air only see channel 1 and 2 or right and left. We want to live record 4 people using the Scarlett 18i8 as the input device and then feed that into Camtasia or Google Hangout on-air which only sees 2 channels. Right now, it seems that Camtasia and Google Hangouts on-air only "sees" or "hears" the 1st two people, line 1 and 2 but not the 3 and 4th. What Focusrite Scarlett said is I need some type of "virtual mixer, where you can take multiple inputs and then send out a stereo output. Your software would then be able to then and record it." I think I understand but don't know where to go next to make it happen.