I'm sorry I didn't get back on this to you.
I asked about the mod file because we found that under XP ('emulation'), MikMod will gladly play simultaneously with other apps (you can hear sounds while playing WinAmp too, so that's only logical). Under WinCE, this is not the case. Playing a sound blocks the audio system for other sounds.
We used to play samples using the WinCE API, not MikMod. I'm not sure how the current situation is, I'll look into this. But if that's still the case, you wouldn't be able to play sounds AND play music. That would be easy to fix though.
Then again, it looks like that is NOT the problem, since you are playing without music.

Could you tell me what the frequency is of the sample you're trying to play? I noticed that odd frequencies don't work well...
- Jacco.