My outdoor GFI outlet keeps tripping. I think it could be faulty wiring. I just bought the house so I am still learning things about it. I went to test one strand of xmas lights and when I wiggled the cord in the outlet the reset button popped out. I reset and hung all my xmas lights and everything worked fine for the first night. Today they are on and after a few minutes, GFI trips. I have no idea what is causing it. I plugged a lamp into to it and when I wiggle the wire, GFI outlet trips. Do you guys think it's a bad GFI outlet?

Are you wiggling the iwre inside the recptacle box or are you wiggling the cord from the lamp? I suspect you have a bad connection on the GFCI, are you using the side screws or back stab? Check for tight connections