I notice that at speeds around 40mph the rear passenger door on my '07 ION makes a shuddering noise like helicopter blades. If I roll down that window, the noise becomes really loud, chop!, chop!, chop!!!! .... at first I thought that I had a bad bubble in the tire, but the tire is ok, the car is brand new. I had the shop check it out, they say that this is "normal" wind reverberation, I say bullisht to that. It only comes from that side. There is no physical vibration at all, just the noise. Has anyone else had this noise occur with thiser ION and have you had it fixed? What is it and other than playing my radio real what is the cure? TIA