After sending my new 11reg Yeti back to the dealer for a second time to replace the windscreen after a leak, the dealer valeted the car as it was smelling damp. On inspection I noticed that the wheel nut covers on my alloys are not looking shiny. Have they used some chemical to clean the wheels and its discoloured the plastic wheel nut covers? (see pic) Should I complain to the dealer when I take it in a-g-a-i-n to look at the rattling speaker after they replaced the Columbus head unit after w