A question for the electricians here:
Here is my set-up:
I have a dedicated circuit from my house's main CB panel with a GFCI CB installed. The circuit runs directly to the outdoor J-box, which is a weatherproof, 2-gang box that houses a GFCI outlet and the switch for the light. Not sure why it was originally installed with both a GFCI outlet and a GFCI CB since I'm not the original owner.
Last summer the GFCI outlet was tripping and I troubleshot and replaced it with a new GFCI outlet to fix that problem. It worked fine until a few days ago and is now tripping the GFCI outlet again. I wired the light switch directly to the line side of the circuit (taking the GFCI outlet out of the picture) to confirm the outlet (less than a year old) is the problem.
I could accept that I have another bad GFCI outlet except that I have had them in other locations in my houses for the last 25 years and have never had one fail. Does anyone have any ideas if something else may be going on; Maybe something to do with the outdoor location (even though the J-box seals look good and no moisture or corrosion inside)? Maybe something to do with having two GFCIs in the same circuit (outlet and CB)? Or just coincidence that I've had only two failures in years and they just happen to be at the same location?