Holy moly... My Core1 MIDI Issues are finally SOLVED... Turns out I had the wrong sized caps in C1_CORE1 and C2_CORE1 (embarrassing). This was impacting the oscillator frequency and effectively crippling core1. I have a big box of MLCC caps, which must shifted around in their compartments. That will teach me to examine those tiny little numbers better and test each component, before soldering!      So, once I corrected the caps, all MIDI communication though MIOS ar