Interesting problem - loud popping and grinding noises from the roof during turns and over bumps - it is obvious it is a broken weld - afraid to drive over even the slightest raises in the road - the car already flexes a lot, but it could be catastrophic faliure. the dealers don't want to look at it - they want to keep the car for several days for "noise" issues. I am sure they will have to replace the entire headliner when they do the repair. (if they can even do it, and if they do, the car will be compromised) But having had many trim pieces fall off, and the drive by wire feature of the throttle staying full throtttle 300ms after the throttle is released, and many other minor issues, I am wondering it what people keep saying about the first model year to be built in Kentucky is true. A friend put up a video of his that includes the audio from the noise (not enhanced) - The video was put up because I have two friends that were unable to solve issues, and one that had a major break booster failure that almost caused an accident a few miles after the warranty expired and they would not help in any way.