Update: I looked over the car thoroughly and found that the windshield is misaligned with the roof glass. The circled area has the roof glass sitting higher than the windshield unlike the rest of the glass. I'm guessing that little lip causes the air to become turbulent at high speed. I went to a local sales center and looked at about 5 MYs and M3s and none of them were misaligned like mine. I showed it to the service center and they scheduled me for a windshield replacement in 2 weeks. Will update again after the replacement. Hoping the frame of the car isn't the culprit.