I'm sure you checked, but when that happened to me, There was a break in the window seal- I added some of that black glue every one uses...It's probably coming from the vents under your wipers, or the lip of your hood,closest to your windshield and blowing into the bottom of you windshield where they don't usually add the black window sealer-Or there are seals in the engine compartment that need checking-It could be coming through the stearing column from where it meets the engine compartment-check all those that come from there to the inside of the car. it's air-it's there, it's gonna be found if you really hate it!..Good luck