There's a neat utility built into Windows called "DirectX Diagnostic Tool". To run it, click Start/Run/dxdiag.exe/Enter.

On the "Music" tab, go to the window at the right center of the app. Highlight each port and click "Test Direct Music". (Note that hardware MIDI ports don't make sounds.) If any issues are found, the result will show in the "Notes" window at the bottom. You also get to hear a really cool MIDI composition and how different it sounds played through various synths.

The "Sound 1" and "Sound 2" tabs run through a series of samples played at different rates in mono and stereo. Again, if there are issues those will show at the bottom of the applet. I mention these last because you already know it's in mono and maybe the above will show something. But I'd run these, too.

The "More Help" tab has links to various troubleshooters.

You can also test other systems on your PC with this utility.

HTH,

R.

"My primary musical instrument is the personal computer."