That would be interesting. I have in the meantime found that using an HDMI - HDMI cable really makes the issue better but it does not completely go away. However, it lets me work and I don’t care too much. Would be interesting to see if the higher quality HDMI cable does the trick. This one literally says amazon basics on it, so I guess it’s a basic cable 
One thing that always makes my monitor flicker is using a HDMI to DVI or HDMI to VGA cable.
Either way, with the HDMI cable it still seems to mainly happen when the CPU is loaded and it only happens when the computer is plugged into the power. Does the house have dirty grounds: I’m fairly certain it does, no proof, but it’s hard enough to find a ground at all here. Does it happen with my work OSX and HP laptops that are now all here, nope. Still love my Librem!