This radio was installed professionally. Everything is fine. And I can get all my FM stations just fine. But when I hit the "source" button and go to AM, I can't pull in anything. I know the car's main antenna is plugged in because all my FM stations are perfect. And in the "Menu" functions, I have the AM selector switched to "ON" but still, not even our major 50,000watt AM station will come in at all. Thanks.