prolly is the speakers dying i guess but also maybe your radio just lost a channel or whatever...my stock 95 radio would play okay when playing the radio but no sound from the right side when playing tapes....i bought a radio from a 97 tour from someone on this site (for 5 bucks plus 7 for shipping) and installed it....works like a charm now and sounds pretty good...it was also basically brand new since its o.g. owner pulled it out pretty quickly after buying his tour new
my car sounds so good that i am now officially qualified to say 'fords stock stereo system sucks'