I don't have problems with 1440p or 4k with Port 4, however i`m using PC, 120hz will fix the issue if you are not using "standard VRR", however if you use VRR with LFC( low framerate compensation is repeating every frame when frames are below 60) you will be able to mitigate the issue as the refreshrate of the display will stay nearly at 100hz+ all the time. I assume next gen consoles will support LFC as well so you don't have to worry about it.Out of curiosity did you run 120hz/1080p on port 4? I know port 4 doesn't accept 1440p and the other ports also have VRR. I'm stretching obviously but I have seen multiple pc users claim 120hz "fixes" this issue. The thing I haven't seen anyone do is limit fps to 60 in game while running 120hz with VRR to behave like a console. I don't understand how 120hz could fix this issue if your only running 60fps VRR like I would expect from next gen consoles AAA games so my theory has been higher FPS is what is actually fixing the issue. I don't know of any console games that push close to 120 fps in performance mode on a xbox one x, but there might be one.