This is just a
very long distance hunch, but check for corrosion at the grounding point: X10010 GROUND right hand side of glovebox. I expect you will find it on the right wall forward of the door.
If that pans out, I can suggest a measurement you can take and another suspect.
If pulling the glove box will be any kind of bother, you can take the measurement. I pull my glove box so often, I sometimes forget when it is not there.