Are you using Media Player? Or VLC? If the video or audio in your DVD doesn't work at all, it certainly means that you need to update your player with its latest decoder. You need to install them every time they give you an update for installation. You can search on the web to find some free app to download so you can always detect if your player needs an update.
For more info you can check this site :
http://techyv.com/que...layer-no-dvd-decoder.
Have a great troubleshooting day!