I'm have the exact same issues! I plugged in a keyboard into inputs 7-8 of the MOTU 828 mk2 and I'm getting signal in Logic on 9-10 AND on 13-14 (!!!). While my mic input seems to behave normally, the keyboard comes in REAL low. I Haven't found any setting in Cuemix that would change that. I did a lot of searching on Google and found several people having the same problem, but I cannot find the solution. PLEASE HELP!