I had the same problem when uploading my product videos related to gym accessories. I tried the steps you mentioned, like ensuring the video format and resolution were supported by Editor X, which did help a bit, but leather weight lifting straps the video is not being optimized even I tried. I also optimized the video before uploading to balance quality and file size. I reviewed the platform settings to check for any options to adjust video quality. Finally, I considered using an external hosting service like Vimeo, and even cleared my browser cache, which resulted in a little bit of improvement in video quality. Anyways, thanks for the help, mate. 