Just a quick read on your post.
These players have lots of old grease that needs cleaning, I do know that and have heard you need to take everything apart but its
very hard to get back together correct.
Other thing that is my guess is the laser is dirty, don't use alcohol to clean, I believe windex is OK or someone used distilled water
but very careful to not break the laser.
Worst case would be capacitors leaking or starting to go bad.
I'm no tech so do all repairs at your own risk.
I have 2 3070s and have read and talked with other techs about issues in the past.
One of my 3070s is having trouble flipping and I need to one day open and see what it may be, but that's my deal