Service Host: Local System (2) using between 12 and 35% of CPU time

Hello,
I've been having an issue and trying to deal with it a few times. This has been for at least 2 months.
This so called Service Host is using up a lof of CPU which makes my computer run hotter, louder, and even slower.
I have tried sfc scannow, but takes a lot of time and I believe that it's only a temporary fix until restart.
Another solution I've found is going into "troubleshooter" for Windows Update and it fixed the issue until next restart.
To give some context there is now and then "Windows Modules Installer" popping up in the top 3 list of most CPU intensive tasks.
I do not have any viruses installed. I've scanned thoroughly with Malware Bytes and have Avast running in the background at all times.
I've done the "clean boot" technique, it seemed to work (it wouldn't use my CPU anymore) but I don't know which services to keep disabled or so..



Common sight.
Thank you for anyone who would know how to fix this,
KS.

Thank you for the reactions.

I have a few screenshots here:

for TairikuOkami :



Just to be clear I have already made sure (long time ago) that I wasn't uploading updates P2P:



for dalchina:




I've also noticed this here:
I don't know if this is of interest.

I think that it might have something to do with drivers but not sure once again.



Thanks again for helping me out.

When I do Windows Update troubleshoot, this is what solutions it comes up with :

I don't know why there is part of my computer in french and other half in english.. althought I've always selected I want my computer in English.


another example of this issue...

I'm installing the update you linked me to right now, I will reply later to see how it turned out.

Well whatever the issue may be with that I don't mind it that much as I know the 2 languages very well.

System Host: Local System is still using around 13% cpu right now so that didn't do anything unfortunately...