hello I just got a 05 a4 Quattro 1.8t it has 50,000 miles. When I accelerate at about 40-45 I get this noise I can kinda control it with the gas pedal if I accelerate hard it gets more pronounced if I let off a lil bit it get sorta quiet if I let off all the way it gets louder. It almost sounds like something is dragging on the ground. It's a flutterin rattle grinding kinda all them depends on how hard I push the gas. I had it a week. It has a new exhaust on it and new brakes. Any help or advice or anything will be greatly appreciated. Thanks my cell is 440-251-3500. Anyone can text me any info they have. Thanks very much