It is about my 2017 RR SC with 21K miles. For about last 2000 miles sometimes I feel the car vibrating just as if one of my wheels was not balanced. They were perfectly balanced recently. Typically, I leave my house for a 10 miles trip and everything is perfect, a very smooth ride. On the way back I feel the car vibrating at speeds above 50 mph. I would stop, turn off the engine let the car lower itself, then start again but no improvement. I took many long trips (1,000 miles) with no problem. One of the last trips driving in town, I got warning 'Adaptive Dynamics Fault', AEB Fault', and Suspension Fault, do not drive over 30 mph' all at the same time. When I drove to the dealer service everything was fine. They looked at the vehicle but could not find anything. Last time when I took it in again, they could not find anything and recommended to install a recall for the Adaptive Dynamics. The intermittent vibrations did not go away. The biggest problem is that when ever I take the car in it works fine and they can not find any problem.