Sergey Biryukov

Recent minor updates for WordPress introduced a couple of regressions when uploading audio and video files:
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On WordPress 4.3.x and earlier branches, audio/video files cannot be uploaded at all due to a fatal error.
Full list of affected versions: 3.7.19, 3.8.19, 3.9.17, 4.0.16, 4.1.16, 4.2.13, 4.3.9.
This will be fixed in the next minor update, see the <a href="https://core.trac.wordpress.org/ticket/40085" rel="nofollow ugc">Trac ticket #40085</a>.
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<li>
On WordPress 4.4.x and later branches, audio/video files are uploaded with corrupted thumbnails.
Full list of affected versions: 4.4.8, 4.5.7, 4.6.4, 4.7.3.
This will be fixed in the next minor update, see the <a href="https://core.trac.wordpress.org/ticket/40075" rel="nofollow ugc">Trac ticket #40075</a>.
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</ul>
In the meantime, this plugin is a workaround that solves both issues and restores the upload functionality for audio and video files.
Don’t forget to remove the plugin once the next minor WordPress update is available!

Correct Audio/Video Uploads

Restores the ability to upload audio & video files in recent minor WordPress updates.

Sebastian Krysmanski

By default, WordPress only allows a very limited set of file types to be uploaded. This set is defined by a so called 
“white list”. What’s not on the white list can’t be uploaded.
This plugin allows you to extend this white list through a settings page.
Additionally it comes with a wide range of file types that are enabled automatically, like audio files (ac3, mp4, …) 
and video files (avi, mkv, …).

Upload File Type Settings Plugin

This plugin allows admins to specify additional file types that are allowed for uploading to…

Correct Audio/Video Uploads vs Upload File Type Settings Plugin