95 riviera radio goes "Pop"

When I turn the radio on, it works normally for about 5 seconds and then there is a pop and the sound goes off. The volume and the station still display. When this happens, the CD player works barely (scratchy and in and out) and the volume control doesn't work. Any ideas?

My 1989 Riviera does the same thing. They told me the Bose amplifier that is hooked up to the stereo is bad (bad resistor or something like that) and it needs to be replaced. Best bet may be a junkyard.