Codec issues with plex

After having some issues with plex that seems to revert back to either audio or video codecs and the lack or inability of plex itself to use or deal with these codecs it seems to be that this could be a major issue with the system.

I always seem to have no sound when the EAC (I think) is needed or used in movies etc. Also there seems to be something with video codec or transcode issues. the main one is that the video froze, the audio kept going. VLC had no video issues and played through without a problem. Now I did replace the movie file in plex with a different version which played fine in both plex and VLC. Still confuses me that the original one froze in Plex but not VLC at exactly the same spot!

Overall I think that plex is a brilliant media organiser and player etc but it does need to have its own available audio/video codec library to call on so that no matter what gets downloaded or thrown at the media system then it can handle it with no errors or issues. VLC seems to do this.

I would like to see an audio/video codec library added that can deal with all audio/video types.