Maybe I'm overthinking this, but I'm not clear on this point:
If each DIN source is a physical i/o pair, do two DIN devices each need to reference the other in iConfig for bi-directional MIDI? Or would that cause MIDI feedback?
DIN1-FCB1010 controller -->DIN2-Adrenalinn gtr module
DIN2-Adrenalinn gtr mod-->FCB1010 controller