On paper yes - everything should be checked.
But in real life....
As I've found out, this is more compatibility issue, rather than hardware fault.
12th gen intel processors lower their operating speed at low load with different algorithm, so not all types of RAM modules can follow this (this is why it happened at low load) Most likely, when you type in text and studio has to change it to blue color, there's microscopic change in CPU speed, and RAM can't follow it.
I had PNY branded ram, replaced it with ADATA and it works fine. These PNY modules also work fine with the different computer (AMD 3000G).