I see this come up a lot, and its a pretty simple fix if anyone wants to get rid of that annoying air sound that only seems to come up at highway speeds.
(At least on mine)
Basically, with the frame-less windows, when people shut the door with the window it eventually bends it out of shape, sure you can shut the door with the door, but most passengers (where my leak always is) tend to shut the door with the glass as its arm height. Whatever, like I said, simple fix.
Basically, roll down the window making the noise, and squeeze together the two sides of the gasket. Where the speaker is and where the mirror is (at least on my car) Squeeze it and hold it for a moment, go ahead and do it in a couple places, I've never overtightened this thing. When the window goes up it will push it back to the shape it needs to be if you overdid it.
That's it. If you roll the window open and you notice on either side the gasket isn't forming a 'seal' on the window, its definitely your culprit. At this point I think I've over complicated the explanation because I've spent 4 paragraphs explaining what a picture can do easier.
I've found myself doing this twice a year and it fixes it fine. A super temporary fix for me is to roll the window all the way up, and just barely tap it down, this somehow pushes the window out some and forms the air seal to shut the window up.