I posted on here a few months back about a high pitched whistling noise that starts to sound in my car at speeds above 40mph (2.0 FSI). At the time there were suggestions that it may be a window not sealing properly. Anyway, the noise became less severe over the summer, but has now reappeared - just as the weather's become a bit cooler. I was convinced that it was coming from the engine compartment somewhere, and in my desperation covered the front grille with newspaper and went on a test drive. The noise stopped immediately! When I removed the newspaper, it started up again. So it's definitely air coming in through the grille and hitting some component under the bonnet, and it's possibly linked to the outside air temperature. Any ideas as to what this is would be much appreciated! Last winter, Audi adjusted the plenum chamber cover, the bonnet catch position, and the wiper arm position but no success. Incidentally, I have to say that I've become increasingly dissatisfied with the number of rattles, squeaks and knocking noises in the car during my first year of ownership. Two rear seatbelt reels are about to be changed as they continually rattle, a component on both rear shock absorbers was replaced due to a knocking noise, there is a rattle coming from the drivers door which I can't locate exactly, and the drivers hand grip rail rattles too. Or perhaps I'm just being too picky?!?!