Strange noise when back windows open

I've had my kuga now for 2 months and have noticed that when i'm driving more than 30mph and the back window is open i get a vibrating funny noise that is so hard to described but it make you feel ill like it's going through your head and i have to close the window, it's not the radio vibrating because it still does it with the radio off, my husband thinks it's just a bad design fault, does anyone else have this problem or is it something i did to discuss with my dealer?

Edited by Lisa27 - 27 Jul 2010 at 11:06pm

Try opening the drivers side window a bit, as this resolves the issue for me.

Thank you everyone, even if it can't be fixed at least i know how to manage it and my kids can have the window open if they want to.  It is very strange though.