Vintage Synth Repair

I had one keyboard here that would only play thru on the B note, every
octave though.
Thought at first it was a comm error from the keyboard lines to the
M50734 chip.
It wasnt. All notes were making it from the interface board to the
6850 chip on the main board.
I took out the main board  and reflow soldered he leads for the 68000 uP
and the 6800 peripherals.
Problem gone.

YEAH!