To clarify - with the MIDI shield, you can forget about using pins 0-7 for anything, and I was stupid enough not to wire pin 0 (receive - RX) into the arduino,
I soldered a header to connect the MIDI shield to the arduino, and it works now. BUT - I was using a M-M header I had lying around. The lack of stackable headers with the MIDI shield is a silly omission (since you have to solder everything else onto the board) but who gives a *$£# - they don't make them any more.
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