BMW 3 SERIES ISSUE

I Purchased a BMW Brand new from BMW SMG PMB. A week after delivery I complained to the salesman that when you drive the car it sounds like the window is open. This was August Last year.<br> The vehicle has been back n Fort to SMG several times.<br> There was a modification don on the mirrors<br> Then there was a new slide fitted.<br> However the problem still persists. When I complained back to BMW , The response I got was as follows<br> <br> I quote \ The vehicle is designed like that to make that noise