When exporting a video from Premiere Pro it makes a .m4v file instead of .mp4, even though it saids in the Premiere Pro that it will make a mp4 file - and I can't use them afterwards. It has been there after I have updated last time.
Turn on multiplexing. .M4V is a video only file (without audio, which is in a separate file).
Also, make sure that you check the box marked "Export Audio" if you want a MP4 extension.
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