TV only powers on when spamming power button

Hi,

Model number: LG OLED65B9SLA

So my LG OLED TV has developed this problem, where I have to spam the power button for several seconds for it to eventually power on. After roughly 10 seconds the power supply will start clicking, like you'd expect, and the TV will power on and function perfectly.

I've removed the back plate to look for any obvious causes but nothing looks burned or the like.

With the TV on the table and spamming the power-button, I can hear the sound of some component charging up, on the main board, higher and higher pitch sound with each press of the power button until finally the power supply wakes up and the TV powers on.

If I turn the TV off, I can hear a component (perhaps the same component) in the same area constantly ticking (3/second) indefinitely. If I do the usual hardware reset of holding down the power button for 10 seconds (to ground the capacitors, I'm guessing) the component whines a little and the ticking stops.

My best guess is, that the start-up circuit on the main board is fried. My logic being, that if it was a power-supply issue I would have other issues when actually using the TV, but like I described it functions perfectly once it's on.

Here are some videos of the noises:

Spamming the power button:

https://youtu.be/-NisFsx6x14

Holding power button to reset:

https://youtu.be/E0mv6Dx98xA

After shutting off the TV:

https://youtu.be/YS7FLEIFdR0

Edit: Forgot to include the pcb numbers:

Power supply: EAX68364701

Main board: EAX68784905

Edit 2: Included close-ups of the PCB pin information:

Connector for the main board

Connector for the panel controller

• UPDATE AND SOLUTION BELOW ***

Alright, time for an update. I'll try and keep it short but I'll answer any questions.

I ordered a new motherboard for my TV and while waiting for it to arrive, one evening the TV blew the fuse in my apartments fuse box, before blowing its own later. This led me in the direction of the faulty board actually being the power-supply, despite my initial findings. I ordered up a new power-supply as well, installed both components and the TV now functions flawlessly again.

The new motherboard is identical to the old one.

The new power-supply has some differences. I'll include some pictures below for comparison.

Another finding, the noise I described in my initial post, from a component on the motherboard is still present with the new motherboard and power-supply. It's probably just normal and only something you would ever notice if your TV was acting up.