Said that it changes the speed of the airflow around the mirror. Stated that testing has been done with/without PPF. I was quite shocked to hear this. Not sure I believe it either, but just reporting what they told me this morning. I’m 100% PPF’ed.
My car is a lease, I have neither ceramic nor PPF. I had no whistle for over a year, then it just showed up one day. No idea what changed, but it wasn't any kind of coating or film.
If not already done, perhaps this TSB will solve your wind noise problem. It solved mine.
Job: TSB-C0324-005-01 Loss of retention from Side Door Glass Run Seal
Concern: Client states the driver rear upper run channel molding is popping out. Please check and advise. Confirm proper fitment.
Cause: The side door glass run seals lose retention and separate from the door frame.
Corrections: Performed -TSB-C0324-005-01- Install retention clips on all side door glass run seals.