Yeah, don't do that.

I had a problem with MIDI's when I moved from 98 to XP.

The way I fixed it was turning up the internal volume. I noticed it when making MIDI's in Anvil Studio. Go to www.anvilstudio.com and download the program.

Load a MIDI that won't play and on the Composer page of the the program turn up the internal synth volume and save it. It should work. But don't get your hopes up.