Hello and Welcome !
First i would recommend to uninstall Program such as VLC, K-Lite Codec a.k.a Media Player Classic then reboot the System the install Shark007 Codec Shark007.net - Windows 7 Codecs - WMP12 Codecs and test it.
Hope this helps,
Captain
I can only talk of m4a files. I too have installed k lite codecs to play these files and all works good. Also wmp tag plus allows playing of m4a files (might be a more updated version of this). If you want to use both itunes and wmp for your music collection be careful as they may conflict in the way they are formatted. Itunes very sensitive in the way files are named.
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