Line 6 M13 Not Powering on.

[morgs]

Gday all.

Hoping for a little guidance here for my novice brain.
I've tinkered with valve guitar amps in the past and have a basic understanding of some of those types of circuits, but I'm a little lost when it comes to solid state + digital stuff.

So here I have my Line 6 M13 Modelling Stompbox. No worky.
My first thoughts are start at the power rails and work from there.
Have 9vac to D8-12. No dc after that.
Diode test showed 0.574v one way, open the other. When performing this check they all tested short momentarily and I watched the voltage climb to 1.9v before showing open.
Continuity test across capacitors c81,c84, c82,c85 + c80  showed open, but again initially were short until voltage increased and then showed open. If I repeat the test, they show open immediately, however if I reverse the leads it'll read short momentarily and then open.
All these tests were done in circuit.
I'm thinking my meter is charging the caps before they show open and this is effecting the diode readings also.
I don't currently own an ESR meter ( ordered and on its way ) so I can't check the capacitors definitively.
For the sake of a few bucks, I'll probably change them out anyway. They would be about 10 years old now.

The rip out and replace option may fix the problem, but doesn't really help me understand what's going on.
I'm guessing I don't really have all the test gear to fully diagnose the issue, but any guidance would be much appreciated.
Hopefully my logic isn't too flawed, however I'm all ears and happy to learn, if that's the case.

Cheers