There is a major problem with all of the capacitors in your radio. When they start going bad there are lots of things that can happen. The most common is dc offset which can damage some or all of your speakers. I would reccomend talking to Cleeve in my repair shop as he has rebuilt units he can do an exchange for you and send it to you. He is at
www.lajollaaudiorepair.com
Scott@lajollaaudio