I have my Sonos System (Ray, Sub Mini, One, One SL, Boost), connected to my Samsung TV. 
In the App, only TV is listed under “Your Sources”; Apple Music and Sonos Radio are listed under Your Services. 

The issue occurs while watching TV. The system starts playing the TV Audio when the TV is turned on as expected but at least once per viewing session it will switch from playing the TV audio to play the music services instead without being prompted. To play the TV Audio again, I have to open the app and reselect the TV source.  

How do I stop my system from switching from the TV Audio source to playing music without directing it to do so?