Hi gotsisu, Sorry for the inconvenience. AM definitely requires a good antenna connection and a good ground to the unit. FM is more forgiving. The good news is this should certainly be resolvable. The easiest thing to try would be a test antenna to determine where the issue lies. An old fashion automotive antenna at the auto parts store would do. Simply remove the side trim pieces and the mounting screws to slide the unit out of the wall. Antenna plug is on the side of the unit.
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