I think all these special installation operations, that are way too complex for me to understand, shouldn't be necessary as all the software is already installed. Potplayer (my main video player), VLC Media Player and even Windows Media Player all play these m4a/aac files without any problems.
The source code of Potplayer (
https://sourceforge.net/projects/potplayer/) and VLC Media Player (
https://sourceforge.net/projects/vlc/) are available.