I've never had any luck getting those things to work once they quit. I've got an idea though, before taking it apart, spray inside it with wd40 or liquid wrench to see if that works. I would gently bang it on the workbench also. On the unit on my tank, it has a small screw, try tightening/loosening that to see if that gets any results. Mine changes the tone slightly or makes it stop. I would think another buzzer part could be spliced in to the holder as long as it's the same voltage, one or two batteries.