Hi, I've a 1999 R129 where the windows should drop about 1/2 inch when opening the door and then move up again when the door shuts; sadly this has stopped happening and the glass is now shutting against the outside of the rubber. Also the 'one shot' opening of the windows has also ceased to work. Both windows do still open and close by holding on to the button. Can anyone help before I have to resort to the dealer? Steve