It's definitely something to do with the rotation of your wheels then. I once got a crushed beer can stuck in between the wheel and the brake caliper.
I'd suggest a good visual inspection. If metal is hitting metal, you must be able to see something.
Nick / TopDownInFL (sans the "top down")
2017 540i - Carbon Black Metallic | M Package | Lots of bells and whistles
2012 650i Coupe
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