I recently purchsed a 2011 S5, I have questions for someone who has an automatic. When I take off in the car at a steady pace I hear a flutter type noise coming from under the car, possibly the exhaust system. The car drives perfect no misfire or hesitation no engine light on....I have contacted multiple service techs they all say this is normal. I did speak to one tech that was describing it as the air flow through the exhaust system or something to that effect I can't quiet recall the exact explanation he had given. Is anyone familiar with this situation? Please help....by the way everything on the car is completley stock, 2011 prestige with sport diff.