If the "Media Feature Pack" does not appear in your search results under Optional Features, check the following: Media Feature Pack for Windows N - Microsoft Support

Windows will now download the necessary files from Microsoft Update and install them automatically. You may need to restart your computer once the process is complete.

You may also need the HEVC Video Extensions from the Microsoft Store (some MP4 files use H.265). Also, restart your PC twice (a full shutdown, not just a restart).

If you followed this guide, your Windows 11 N machine is now fully media-capable. You no longer need to struggle with silent alarms or unplayable videos.