Video streams randomly turned off

I did a small test today. One VM with 1 physical core (no hyperthreading) and 8 GB of RAM. During the call when we were seeing people faces, the quality was good. The audio was good across the test. But what I found weird was that the video stream from participants was randomly cut off.

The person who was speaking always had his video stream active. But for other participants, their video streams were very often replaced with their first and last names initials.

The only config I did to my server that seems related is disabling simulcast.

disableSimulcast: true

Unfortunately, i did not capture the CPU behavior. But is this a known behavior? How do I prevent it from happening?

This will dramatically increase bandwidth usage on the server and at the participants side. So loosing video when overloading clients download links is to be expected

Interesting. But without that config, the quality of the video was a little bit underwhelming. So I have to remove that and see what happens. Anything else I can do to increase stream quality without disabling simulcast?