I had something similar to this after about 1,000 miles on the car (I have almost 2,000 now). A faint double clunk or click on startup from a stop, and sometimes a clunk when slowing down. That's what it sounded like with the windows closed. Pretty faint but this car is so quiet that we tend to drive around with the windows up and no radio just to admire the silence. Also it was very hard to tell if it was coming from the front or the rear, right or left. I stuck my head out the window to see if I could tell where it was coming from and the sound was different. Still pretty faint but a slight jangle, like somebody hitting a tambourine. I took it to the dealer and they torqued the drive shaft, which seems to have solved the problem. They have submitted some kind of inquiry to the factory about this because they had never encountered it before and were not completely sure that they had permanently solved it. Nice that the service department is pro-active. My only other issue is a stuck fuel door. Very hard to open you have to push it very hard or punch it several times to get it open. The dealer has a new one on order.