Karl Ellison wrote:

> Is it acceptable to put a _tiny_ drop of glue (hot or white)
> on the pins side to prevent it from working it's way out again?

In a word, NO.  You can either fix a problem, or try to fix the
symptoms.  The pin has to be free to turn in the felt bushing and at
the same time fit tightly in the jack so it doesn't slip out sideways.
Repinning is not rocket science, but it requires a learned "feel".

Call a good piano technician, it is probably time to get the piano
tuned anyway.  Where there is one loose pin, there are usually more.
A technician can find these and fix them properly, saving you a lot
fiddling around and, almost inevitably, grief.

Jurgen Goering
Vancouver Island