Fairly certain the issue is with a low quality MIDI cable. Opened it up, and its just directly mapping pins with no actual circuit. I've found threads that there should at least be some sort of simple circuit with an optocoupler. I snipped off the game port in and midi in cables, and that improved …

Hey there, first post, but I've gotten tons of great information as I put together my first retro PC rig. It's a Optiplex GX110 with a P3 500, 256MB of RAM. On one disk, I'm running DOS 6.22. I've got a Labway OPL3-SAx (which has the MPU-401) and I'm having difficulty getting it configured to …