I bought a new c 220 d September 2015. from the first month a rattling noise comes from the windows. started driver side window then other side now in back also. reported to Warrington Inchcape and they said it is some seal problem and I left the car 3 times with them to sort it but the noise is still there. I realised that the same sound comes from courtesy car as well. Is it a common problems. can it be rectified.