So we have had our CT about two weeks. My wife drives it during the week and I drive when we're in the car together. I had a few too many Sangrias at the family Xmas get together so my wife drove us to our in laws afterwards. She rolled down the back two windows for the dog and immediately a loud painful reverberation vibrated through the car so loud I started to think it was that front vibration some people on the forum have mentioned happens at 20 and at 70 mph on some cars. Then we realized this happens on some cars when the windows trap the air coming in. I don't know exactly what or how it happens I just know you have to crack a front window or the sunroof to make it stop. You can always roll the back windows up instead. Anyway, just glad it was not something serious. Does anyone know if this is a design flaw or if it happens on all cars. Seems to me it didn't happen on the Element but then again the back windows are different?