I am experiencing precisely the same problem as shown on your example video. Same stutter timing, etc. I have tried the various fixes listed but to no avail. The problem has only been present since the latest update. Prior to that there was absolutely no problem, with excellent smooth output.
I am using i5 10600 @ 3.30 GHz and GTX1060, 3 Gb, previously with superb results.
When I switch on Developer-FR graph there is a yellow spike each time the output stalls. Unfortunately there is no indication of what each of the graphed colours represent. Is there an explanation somewhere?