knedlyk the "Allow using DRM PRIME decoder" was already set to No. I attempted a number of other resolution/refresh rates, without success, with exception of one attempt where the flickering didn't happen, however couldn't reproduce this behaviour a second time.
I must note that occasionally the flickering doesn't occur. When it does occur, it doesn't happen on any full white/black/grey screen/areas of the video (i.e. with greyscale colours), its actually the sections of the video that contain colour pixels that flicker. And again, only with Netflix =\