downloads or hefty browser traffic. Sometimes even VPC
sessions caused it, when accessing the network drive.
But never wget in a single thread download.

So, imho wget and only wget could be the culprit as well. I do recall in the past there were quite a few problems with it - after all, it isn't profeesional software.

Whatever you do, still imho, it's mandatory you'll continue without wget in memory (and reboot) to see what happens then.