Got the same issue on my 5.13.
I was before on a 720p TV, and switch to a new 4k Hisense TV, after a lot of issue with screen resolution (solved with xrandr, thanks nadenislamarre for all your posts), I can see the N64 video is not center.
It begins where it should begins on a 4:3 TV but the image is bigger than the resolution, and so I can see only 3/4 of the image, and the rest of the image "disappears" in the right upper corner.
Gonna take a photo tonight, it's better that writing what's happening.
Any idea ?