Power issues with UltraLite Mk3 Hybrid

[soulitude]

I've been having lots of problems with the power supply of my UltraLite Mk3 Hybrid.
For a while it worked sometimes, after fiddling with the DC connector - but now it doesn't work at all without FW.
I just recently purchased a new original power supply, so it's not that.

I took it apart hoping that it could be something visibly broken. But I can't find anything specific.
Measured with a multimeter and noticed that both the DC jack and the pins on the small PCB it's on gets 15V where it's supposed to.

Does anyone have a guess of what this could be?