Ha ha, true enough. It must be disabled before sending those merry music packets out the serial port. But presumably, setting up his SE and using it would be two different steps.

However, what am I remembering about which port MIDI interfaces were recommended to be attached to, and weren't there some kind of port expanders that allowed one to maintain a normal Mac setup without constantly changing the MIDI setup? Or a passthrough switch on the MIDI device, which could be used without a reboot? It's been so long and those were the details I left up to the studio tech ;-)