Hi Andy, welcome to HA. I can't say for certain that this is your problem but most cartridges do not have an unlimited lifetime. There are many flexible parts inside the cartridge body (rubber grommet, metal coils, etc.) that will dry out or otherwise lose their flexibility over time. I'd say a 20-year old cartridge is likely well past its prime. A replacement stylus assembly appears to still be available for that model, but for the same money you could probably replace the entire cartridge with something more contemporary and be sure everything is as new!Of course, I assume your TT is plugged into the "Phono" inputs on the amp and you're taking the output from the "Tape Outs".