Ok. Really I am putting this here so I don’t forget how I did this in a few years time when someone asks me again.
If you use Saorview and have a Samsung smart TV and don’t get sound on certain channels, one cause could be a feature called ‘Audio Description’.
You need to turn this off. To do so, using the remote press the AD button. Sometimes marked AD/SubT.
On the menu that comes up make sure Audio Description is OFF.