jacklink

I have a 99 ML430 with original audio (bose). the radio works fine if not moving, otherwise makes loud popping noises then eventually shuts off or loses reception. this happens regardless of am/fm cassette, or cd. I looked for any loose connections I could see ( green wire under driver seat, and connection to cd changer in trunk). Any other things to check? I don't have the radio removal gadget, but i suppose i can get them somewhere? I do have the radio code.