Have a 99 C280 (just bought it). I noticed that the sunroof wasn't sealing right at the front; I could see sunlight and it was making a lot of wind noise. Then, when I pressed down on it a little from the outside it closed right up nice and tight. Any idea what this is, and how serious a problem it is to get fixed? I'd like to be able to open/close the roof and know it's going to seal...thanks.