SharePoint Online - embed.aspx and stream.aspx not working properly

Target SharePoint environment

SharePoint Online

What SharePoint development model, framework, SDK or API is this about?

not applicable

Developer environment

None

What browser(s) / client(s) have you tested

• 💥 Internet Explorer
• 💥 Microsoft Edge
• 💥 Google Chrome
• 💥 FireFox
• 💥 Safari
• mobile (iOS/iPadOS)
• mobile (Android)
• not applicable
• other (enter in the "Additional environment details" area below)

Additional environment details

Every tested browser

Describe the bug / error

We have problems with embed.aspx and Videos in SharePoint. We have a document library with folders. These folders have some special permissions set. When we embed these videos via "https://tenant.sharepoint.com/sites/sitename/_layouts/15/embed.aspx?id=https://tenant.sharepoint.com/sites/sitename/VideoStreams/folder/filename.mp4" it sometimes works, sometimes not really. Wether using it embeded somewhere or just opening in the browser. The result is always this:

Its really random, some files in the folder are working properly, and some are not. Sometimes we have this problem even when just clicking on the file name in the library itself. The browser opens a new tab with an url like this:
https://tenant.sharepoint.com/sites/sitename/_layouts/15/stream.aspx?id=%2Fsites%2Fsitename%2FVideoStreams%2Ffolder%2Ffilename%2Emp4 and results in showing this:

The direct link (path) to the videos, which are not working as embeded, is working.

Steps to reproduce

I don't know how to reproduce this. It looks kinda random.
Maybe create a folder in a document library and upload some video files.

Expected behavior

We expect that every video is shown and rendered properly.