Hi, I am having the same problem. I have tried what you suggested but the problem persists. It is happening to me on my pc on videos that are downloaded to my computer. The video types are MP4, but I have other videos that are MP4 and I can skip just fine, although they are not similar in length. The videos that I cannot skip are longer than the ones I can skip. The videos that I can skip are less than 5 minutes but the ones that I can't are long. Though me personally, I don't believe that is the problem. The difference in the videos as well are the ones that I have recorded with OBS plus MP4 I cannot skip. I have videos that I have recorded with OBS but are not MP4 are able to skip. Also the videos that I have clipped with GeForce Experience that are MP4 are able to skip. I have tried Moves & TV as well as Media Player and I am unable to skip, select a point in time in the video, or alter the speed of the video. So basically,
OBS + MP4 doesn't work
everything else does
MP4 clips, and other OBS recordings with other video types work.
Hope this helps, thanks.