sounds like its then belt only dose it at an idel just touch the pedel it goes away i have a 2.8 with 81500 miles i was planning on doing the belt ect. come spring also it only seams to do this when its wet out think it could just be water on the belt? any one els run into this problem? its annoying it dosent make the nosie driving but it in my head and i think i can hear it its an audi i dont wanna be stop at a light and have some one hear it with the audi name on the car