Hi Karl, My first thought was also the keyboard lock. After use,
you're supposed to turn it off so you can play the piano manually.

_But as a general rule_, the folks who designed and built these
mechanical musical instruments -- built by the thousands over 100
to 200 years ago -- knew a _lot_ more about them than you and I do,
after owning something for a few years.

I've restored dozens of music boxes, organettes and crank organs over
the last couple decades and the _last_ thing I want to do is try to
alter some facet of the design.

You wouldn't believe the stuff I've removed from an instrument --
how about using a plastic raincoat instead of bellows cloth in an
organ or organette. Or using modern Phillips screws or sheet rock
screws to replace the original steel screws.

Good luck,

Craig Smith
Upstate New York