I had this problem which I noticed more after I went in my mates Ibiza Cupra, which didnt make the whistling noise.
Had it into Seat about a year ago now suggesting what it was, they either replaced or added another rubber grommet to the somewhere around the hinge joint on the Drivers Mirror.
Problem Solved! No whistling at all.
Regards
Nick
Had it into Seat about a year ago now suggesting what it was, they either replaced or added another rubber grommet to the somewhere around the hinge joint on the Drivers Mirror.
Problem Solved! No whistling at all.
Regards
Nick