Honda Accord 2003 AM radio garbled reception

My 2003 Honda Accord has a 6 CD changer/FM, AM radio. Recently the AM reception has become garbled and sounds as though there are 2 stations on the same frequency. My FM reception is OK. Anybody possibly know what this is and how to fix it.

Thanks in advance,

Steve Its been awhile since I've messed with radio's and speakers....but some radio's have an antenna trim adjustment screw on the back....if I remember right? Car Repair Talk's forum.