I have a friend who has post lights in back yard near pool. they are controlled by a dimmer switch inside the house. When the dimmer is at full brightness or the dimmer is replaced with a standard switch, the GFI trips. When the dimmer is at approximately 75% and showing 95 volts at the post lights, the GFI won't trip. The wiring installation is horrible and I have already corrected some issues but this remains. I am going to do more testing but I wanted to know anyones thoughts on the information I have so far. Thank you!