stock radio question

I have a first gen with a left speaker that will go out intermittently. I can sometimes make it come back on if I move the air selector or tap on the dash right next to the radio. It is a stock radio with stock speakers in the doors. Do I need to replace the speaker(s)? Or the radio? Or both?

 

My guess is that's it's a loose connection on the back of the radio or a wire with broken/frayed insulation. You won't really know until you take it apart. I'd pull the radio and make sure all the wires on the harness look good and are secure.

Good Luck.