Peplink MAX HD4 power issue

We have 3 peplink MAX HD4 and today i had i strange problem, that I can’t really find an explanation of. Maybe someone here have seen the same?

The router was running smooth all day yesterday and today, until I plugged a big PC in one of the ports. It had been connectes previosly another place in the network, connected to a sub (cisco) switch. As I plugged it in the peplink, the complete peplink went dead and only the power and status lights flashed randomly. As soon as I unplugged the PC again, the peplink went back on, rebooted and went back to normal.

I checked:
Cables - both tried another cable, and measured cables with a network tester. It’s 568 A wiring

Grounding - both peplink and PC is grounded in the same power plug

Other devices in the ports works fine.

PoE is turned off in the peplink

It seems like the NIC in the PC were toasted when this happened, couldn’t get it working in other switches afterwards.

Any ideas ?