Sony TA-E77ESD Needs Repair - Any Advice?

Try contacting Joseph Chow of Audio Horizons. He also has a repair/modification company called Component plus, he can tell you whether it's worth fixing or not.

http://www.audio-horizons.com/pages/componentplus.html

miko71, thank you for the reference. That's what I was looking for - someone who still services these old units out of the love for keeping them going. 

I'll contact him - seems like my only hope. 

Please let me know what you find out!

Keep us posted should you consult -Joseph Chow.

I contacted Joseph and he responded quickly. Not necessarily offering repair service, but he gave me advice to deal with the static on the volume knob: using contact spray inside the volume pot.

I removed the cover and unfortunately found that the volume pot on this unit is sealed in a square housing, and is rather difficult to reach. I did manage to get the contact cleaner straw inside a little hole in the housing and spray a few shots. It apparently was enough, as the static is gone now.

Haven't asked him yet about the sound processing issue - but I imagine that will be hard to fix as it's so intermittent. The digital inputs have never worked and obviously don't hinder the use of the machine.