Ok here is a full logs with debug enabled and this happened this morning when I was sleeping.
The problem occurred between 0 am and 7:30 am of 2018-12-29. Any error after that time was my maybe closing the process or shutting down the server. And before that time I was awake and the bug was not present.
I checked the logs and there is nothing, only some connectivity loss to plex server caused by remote server that fixed itself a few seconds later.
2018-12-29-08.30.Logs.rar (2.2 MB)
also opened the Process Monitor (during the high cpu usage) to check if there was any unusual activity but didnt understand very well. only registry reads and some local connections.
Here is the Stack Summary from process monitor. Maybe you have some useful info here:
