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The user interface in v12 has one absolutely terrible (though minor in the scheme of things) UI change, which is that the black "Favorite" star for radio stations now sits on top of the thumbnails themselves, so that when selecting a radio station from favorites, it is inevitable to accidentally tap on the Favorite star, which instantly un-favorites the station and removes it from the screen. I'm not sure if this is related to what you're experiencing, but it's a UI fail that I hope and expect Tesla to fix soon.