USB to ME-1

Hello,

I have been trying to run tracks off my computer through USB B. Audio is not getting to the ME-1s.

Channel strip picks up signal.
Our wireless IEMs on Auxes can get the signal.
ME-1s are silent.

I have also tried tie lining the USB I/O straight to the ME-1 I/O, still nothing.

Tips? Direct outs? setting I am missing?