🚀 go-pugleaf

I've been having an inordinate amount of trouble getting my Amiga MIDI
setup working.  Everything used to work fine, until a little while ago
when I accidentally plugged my MIDI interface into my powered-up
Amiga.  There was a bright spark, and following that the MIDI refused
to work.

Nothing strange so far.  Except that my modem still worked perfectly.
A friend of mine said that the MIDI protocol uses a subset of what
a modem does as far as RS-232 signals go.  So theoretically, shouldn't
the modem NOT work if there was any damage the the serial port?

I swapped my serial and parallel CIA chips, just to see if one had fried.
No dice.  Same result.  The results remained even after using A)
Different MIDI interfaces, B) Different MIDI cables, and C) A different
synthesizer.  All throughout this, the modem still worked perfectly in
the same serial port that the MIDI was flouting.

The only further clues I have is that every now and then, for no
explanable reason, the MIDI will suddenly come to life for a few seconds,
registering input on a MIDI monitor program on the Amiga end.  Then,
invariably, it will freeze up and cease to work thereafter.

Does ANYONE technically inclined have an inkling of what my problem is?
I'm at the end of my proverbial rope here.  Any EMAIL suggestions would be
appreciated with fervor.