The titanium plate in Mrs. B's neck does the same thing- naturally, the Docs poo-poo this, but she is more sensitive than the barometer at detecting changes in atmospheric pressure. Kind of like Granny Clampet's "weather cricket..."
Mine, too. C-3 thru C-7.
I noticed that the G&C was working while I was standing in line for Sonny Perdue's inauguration. Stood in line for almost two hours on an open, hilltop plaza with 30 degree temperatures, very high humidity, and a sharp wind. It dawned on me after awhile that my knee and my finger weren't killing me . . . ordinarily I would have been in agony 15 minutes after stepping out of the car.
Oh, well, I'd rather not hurt in the cold and tune in FR or the Weather Channel!