Edward Green wrote:
Okay. I have had very old amps die on me in the past. But it does seem
unlikely.

I wonder if the distortion effect is the same in both channels? Evident
if using headphones, and related to volume? Has something happened to
your speaker's tweeters / crossover?

Perhaps, you were overdriving the inputs without realising you are doing
so? Or negative feedback circuitry component values have drifted and you
are listening to a loverly bit of crossover distortion? Maybe the output
transistors are going... but 10 years? I wonder if controls and switches
are introducing non-linear effects of their own making.

Do a post over to sci.electronics.repair

Yup, I've also got DJ equipment (Pioneer CMX-3000) feeding my HiFi, and
a Rotel separates CD player doing the same. The Rotel player sounds
better but is naff for scatching ;-)

--
Adrian C