I'm in the process of finishing my basement, and am almost done with the electrical rough-in. The whole thing is open studs at this time, so any sort of reconfiguration is easily possible.
I have a 20amp AFCI circuit breaker supplying the bathroom's GFCI receptacle, all with 12 gauge wires. This receptacle then supplies power to the light and fan via a double gang box.
Intermittently and randomly, the GFCI trips itself, but only when either the fan or light switches are toggled. It can go several dozen toggles with no issue, and then suddenly trip. This can happen either with the fan or light switch; I haven't had any luck identifying exactly why this happens.
The GFCI outlet is around 7 years old (came with the house; I repurposed it in the bathroom). Load and line are set correctly, and the switches are also wired correctly.
Is there anything I need to specifically look for, to help identify why this happens, and to avoid it in the future?