this is a older LA spas tub with "advanced electronics" controls, non digital all relay/contactor driven unit.
The GFI trips instantly, even with motor, and heater unplugged, if I bypass it then the tub works just fine but I do get a Buzz from one of the relays, and if I put slight pressure on the contacts then the buzz goes away, i assumed this relay/contactor is bad its a 240v 2 plole contactor and their are 3 of them in my panel the other 2 do not buzz,and i swapped the one and still get the same buzz, from the original position but now the different relay?
or what could be any other cause of the "buzzing contactor and GFI popping???

with everything unplugged except the relays/240V contactors the GFI pops? How can I track it down?

this is the 20 amp 110v GFI that is popping in the control pack.