I don't worry about it, cuz I don't mix for mono
Screw the car...it's one of the dumbest places to listen to music IMO, as the balance and EQ is always way off. Besides, most people adjust their Left/Right and Front/Back balance in their cars to favor their driving position rather than leaving it perfectly centered.
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Well that was an insightful statement, miroslav... my favorite parts are "dumbest" and "most people".