Topic: TM Matrix issue - error in red

Hello everyone,
I'm having hard time configuring RME802 via ADAT with a ferrofish pulse16.
I do record with Logic Pro if that matters.
I'm sending output from rme 7/8 to a hardware stereo compressor and return in input 3/4 adat of the ferrofish.
This creates a weird stereo input out of phase and L/R levels mismatched in terms of volume (hardware Is setup perfectly even, so no HW problem)
If I turn the TM Matrix on on column out 8 i see a Red stripe that highlights the entire column 8. I don't know what that means but for sure something Is routed wrong.
Any insight from all you Expert Is very appreciated!
Thanks!