Two-way recording via USB?

Generally Behringer is not set up to allow for 2 way signals. I don't know about your device but I know it's that way with the Zenyx USB line. In order to do what you want you need to look at the Presonus and Zoom Live mixers. I had somebody help me lay down tracks on a $3K Presonus system and I admit it is impressive once you are fully set up. But unless you have a well equipped home studio and are willing to engage in the learning curve with the proprietary software it's easier to just go the GB route.

Therefore there are two basic options.

a.) You can input the backing track into the mixer like any other line in

b.) Load your backing track into GB or Logic and then after it has been loaded play along with hour next track as you monitor.

There is probably a work around but I think with GB or Logic it's so much easier to layer the tracks and then mix it to taste.