Couple of things I’d check.
First, make sure ARC is actually turned on (I think Sony calls is BraviaSync) so that the Sonos Arc is able to ‘tell’ the TV what kind of codecs it can accept.
Next, check the shows you’re watching. If they are in stereo, then the Sonos will receive stereo, Sonos doesn’t have the ability to change everything to Atmos, or Dolby Digital. Nor do they change the volume of the show, if the engineer has encoded it at a low volume. And because stereo is only using two speakers, not more, it often sounds ‘quieter’.
Thank you.
I can confirm that Braviasync is enabled.
The problem is with SD broadcasts which show up as Stereo PCM. HD broadcasts are fine and come up as Dolby 2.0 or 5.1 and Atmos if in Ultra HD.
Not sure what else can be done.
Maybe they just are broadcast in PCM?
SD broadcasts are only in stereo. That’s an issue with the station broadcasting the signal, not with your TV or the Sonos.
Well, not the stations, it’s what SD means. Limited pixels, limited sound. If the station should be broadcasting in HD, you should contact them and complain.