VW Powered Sound System

I own a '92 Cabriolet and '98 Passat, both are experiencing speaker problems; sound from one speaker only (1 of 6) '92 Cabriolet or from one side only (passenger side; 3 of 6) '98 Passat. It appears to be radio related am I correct?

Thanks

Brad
5 water cooled VW;
'90 5 Spd Passat, '92 Auto Cabriolet, '98 5 Spd Passat, '99 "Old Body Style" 5 Spd Jetta Wolfburg, & '01 5 spd Jetta Wolfburg

i feel that it is a head unit issue, unless you have awful luck with wiring. I have experienced similar issues because the balance and fade controls went bad

Yea try putting in a basic stock radio,
if you have one lying around. If it still continues,
try and re-wire all the speaks, if all else fails
replace the speakers.