I wouldn't suggest you STOP what you're doing - as a semi-retired person myself I charge £25 to fix electrics/electronics
regardless of how long it takes me as 'time' is something I have plenty of (within the confines of the grim reaper that is

).
I was speaking in respect to (potential) frustration - not only to yourself but to those contributing to the thread as you may eventually find yourself to be the only contributor! Looking through the thread I can see this happening now.....
But, specifically, when a thread runs past a given number of pages there will be few people who have the time and/or inclination to trawl through dozens of pages to get a grasp on the situation enough to be able to offer an input - this is why I said I'd 'lost interest'.
It may be helpful (to yourself and others) to break the problem down and have separate threads for each - linking (by posting clickable links) - where it is necessary to join up details.
Even now, as much as I tend to drop in on the thread to see where it's going I (seriously) haven't got the will to review it ALL so assistance, where I might be able to offer it, is sadly lacking.
Might I then suggest you 'start again' with thread(s) titled
DENON AVR - DISASSEMBLING;
DENON AVR - PSU;
DENON AVR - DIGITAL;
DENON AVR - ANALOG etc etc.....
and tackle the various issues
individually where you're more likely to get (and keep) interested parties?
I'm only trying to help!