Question / Help Audio Interface and Mics

[Matt Lubick]

So I have three mics running into my Scarlett 18i20, channel 1, 2 and 3. OBS is picking up only channel 1 and 2 I'm not sure what I need to do to make sure all three are being picked up when filming.

 

[Narcogen]

I could be wrong but I may have read somewhere here that OBS only handles stereo devices-- so two channels per device.