Videos won't play in Preview mode

Hello,

We put together a Rise course with two videos and are having issues getting the videos to play consistently in Preview/using the Shared link. Both videos are MP4s.

It seems to be a random error, happening to multiple users, and we can't find a cause, but the video won't load and we get an error message: The media could not be loaded, either because the server or network failed or because the format is not supported. I've attached a screenshot of the error.

The videos will load and play fine in Incognito mode. 

We have cleared the cache, restarted our computers multiple times, and are using the latest version of Edge. The error is not consistent with the videos. Sometimes it will happen to the first video, but not the second, vice versa, or sometimes both will play without issue.

We know it's not an LMS issue because the issue is occurring in Preview, and the course is not published.

Has anyone else run into an issue like this? Anything we can try that we haven't thought of?