Marcia,  The click you hear, if it is regular and frequent, is most
likely caused from a cracked worm wheel in the governor mechanism.

The original is made of a synthetic (plastic) material and when it
splits, it expands slightly at the split which throws off the spacing
of the teeth at that location on the wheel and thus the clicking sound
whenever that part of the wheel runs against the endless screw.

Replacements are available from Nancy Fratti, or if she is out, I have
a few on hand.  The wheel comes mounted on the pinion, so replacement
is fairly straightforward if you follow the basic rules of letting the
power down on the spring and take things apart and put them back
together in a systematic way.

Good luck with the repair and in expanding your collection.

Dan Wilson
Musical Box Restorations
Raleigh, NC

 [ Nancy has contributed many articles about music boxes to MMD.
 [
 [   Nancy Fratti, Panchronia Antiquities
 [   P.O. Box 210, Whitehall, NY 12887-0210 USA
 [   tel: 518-282-9770  or fax: 518-282-9800
 [   email: musicbox@sover.net
 [
 [ -- Robbie