Using Bose T1 mixer with GarageBand

Anyone have any tips using Bose T1 mixer as input/output interface to Mac GarageBand via USB?

Had been using a Focusrite Scarlett 2i2 channel interface but gifted to grandson. Was working as wanted. Duh.

I'm using a mic thru T1 Ch 1 to vocal tracks. Drag and drop music/video into a GB movie track.

Mac System Settings as I/O to Bose Audio

GB settings the same.

Been playing with individual track input settings (None, 1, 2, 1-2) for music and mic, but keep getting bleed of music into vocal tracks. It worked once, but when I SAVED AS for a new song, added a new music track, I got the bleed.

Could it be in GB Master Track settings or T1 Global settings?

Thanks.