Plex and Sonus Soundbar

When I watch shows through my TV, via Plex on my NAS I only get sound through my Soundbar infrequently. I more often than not find that I have to disable the Soundbar and use the TV’s basic speakers.
Any ideas on how I can get sound through my Soundbar without these issues?

Is there a difference per movie you are watching? or is it the same for each_

The sonos soundbar doesn’t handle DTS or 5.1, it should be transcoding the audio.

Just need to configure the sound options on your client. I successfuly use Sonos 5.1 and it donwmixes DTS to AC3 which comes through Sonos as DolbyDigital 5.1

You can also use your Sonos app on mobile or tablet to identify what source is being passed through (sometimes it appears like surround but can be virtual - big difference). Sonos - Setting - About My Sonos System