Do you happen to have Bass Expension or any other effects from the upper half of the "Player" tab enabled?
Now I'd just like your answer on this question, as identifying the source of the problem will also most likely help fixing it. Also, I'm still waiting for the answer on which VST plugins stopped working in OpenMPT 1.19 and in which way the stopped working. VST support in OpenMPT 1.19 actually got a lot more standards-compliant so this shouldn't be happening, and I really don't want anyone to stick to old versions of OpenMPT.
