It doesn’t seem like Udemy is putting much effort into addressing this issue. I have a finished course waiting to be published where all of my videos are showing up as black screens with my voiceover. The only time the videos display correctly is when I view them in a mobile browser. I’ve seen others with the same issue that has gone on unresolved since March.
Support suggested I use a 16:9 format and although this was already the default format size, I edited each video to specify 16:9 m and re-uploaded each of them. Every time I resubmit, it’s rejected because of this bug. This is getting ridiculous.