I have a 2000 a4 with a stock radio. Sometimes the right side speakers only work, sometimes only the right door. Once in awhile all of the speakers work, but it never lasts. Is this a common problem with an easy fix? Thanks

 

If you don't have an amp, it could be a pre amp issue, contact issue, ground issue, or your uniy is going bad.

I would check the connections at the stereo, then the speakers first.