[ Ref. Scotty Greene in 151121 MMDigest --

Have a clock technician examine the governor and see if it needs to
be re-bushed.  It's a common problem in antique music boxes -- the steel
shafts on which the two small gears in the governor are mounted wear
out the pivot holes in the sides and make them slightly oval rather
than round.  That makes the governor less efficient until eventually it
won't run at all.  Replacing the worn out holes with new brass bushings
solves the problem.

Roger Baffer