My 2013 Outback has what sounds like a vibration in the roof area. Usually starts around 70mph or so. Everything seems tight in the roof rails (which are not extended across the roof) with the exception of a little play in the pieces that can connect across the roof if so desired. I have compared the "play" to other Outbacks and there is no more than any other new one on the dealer lot. Does anybody else have this problem? Sometimes it can be pretty annoying. Maybe the noise is coming from elsewhere, but it sounds like the roof area. If I push on the windows to see if they are vibrating nothing changes. Suggestions?