i had a force II catback put on a good while ago, coming up on a year. and there has been a wierd rattling coming from the back passengers side of my car for a while now. today while idling i was walking to my car and i heard it, (it only really does it at idle, or bogged down below 1k) and i looked between my rear bumper cover and wheel and saw it rattling up and down a little. they didnt weld my mufflers on, they used the clamp, and i havent looked under my car further. waht can fix it?

