2 ideas- you may have road grime on the glass- try washing the windshield with a household dry cleanser WITHOUT ABRASIVES!! I can't remember the brand, but there is one out there. Also, this may sound crazy, but try flipping the wiper blade over- that is take it off the arm and turn it around. Sometimes this settles down a skip or noise related to how te wiper took a "set" when parked.

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Dave

'05 325xi
'10 E70 35d
'85 911 Carrera
'66 911 Work in progress
'91 Chevy C1500
'95 Jeep Cherokee
‘18 Jeep JLU