My metradome key is wound too tight. Does anyone know how to fix this? Thanks, bhfinds

I've heard of this on a collecitble pocket watch... if you can't get the action to start, (shake it, baby, shake it, what have you got to lose?) you will have to take it to a true watch professional. Get references. The spring will most likely need be removed from the housing to relieve the tension. Not something I'd try myself. Get an estimate and consider the replacement costs of your metranome.