Like mohanman mentioned, the culprit seems to be coming from the vent glass behind the A pillar. We've been asked to diagnose dozens upon dozens of these and it always seems to be the same. Depending on cross winds and speed we hear whistling from the vent glass and even the side mirror. We've tried any numbers of fixes but because it's a frameless design, that seal between the vent glass and the rubber seal around the door is never going to be perfect. We just had a few 2020's come in for collision work and they exhibited the same issue still. We're still trying to come up with a fix or work around but haven't been successful. If anything comes up, I'll be sure to post it here!
