First post here. Leasing 2018 CLA 250 in Florida. Hearing a tapping coming from rear, around what I think is they brake lights area. Taps when car is settling out after a turn or slight bump. I think it may be worse when it is hot or higher humidity. Dealer has tweaked and test driven about 15 times and is stumped. Thinks it may be plastic clips or paneling that expands and contracts, tapping against body. Says there may be nothing they can do. Driving me absolutely nuts. Any ideas?