Have you tested Atmos from the TV with another input? Based on what I’m reading in your post, it sounds more like a problem with your PC, particularly the drivers in use, rather than an issue with the Sonos. Unfortunately, I’m really only familiar with what happens on the Sonos, when it is fed an Atmos signal from the TV itself, and not nearly as much on upstream issues. I think I might be contacting NVIDIA or Microsoft directly, rather than posting in these boards for Sonos, as it worked before.

However, if you do feel it is an issue with Sonos receiving an Atmos signal, and not properly playing it, I’d certainly recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it. Don’t post the resulting diagnostic number here, they get sensitive about GDPR.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

Hi Airgetlam (Bruce),

Thanks for your reply and your tips.

I do indeed think the problem is related to the driver of my GPU. But, from some forum, I have understood that the problem is not happening to everybody, and some people have found some workaround solutions that in my case didn't work.

I was considering the idea of a setup problem (Samsung+Sonos), but not being a pro, I can't really judge.

Thanks for your help.

Appreciated.

Not sure I was much help at all, but you’re most welcome. I’ve not seen any other users with a similar setup, much less post a solution, unfortunately.

Ultimately, Sonos has no idea where the data comes from, save it is from a CEC enabled device. So it knows that it is connected to a TV, and is reporting to that TV that it is a speaker that can handle X formats. It is up to the CEC system in that TV to pass that data to other connected devices via CEC (which is what it exists for) on HDMI. 

My concern is your computer may not be responding to / recognizing CEC data (what the speaker can ‘handle’). I just don’t have enough familiarity with either Windows or NVIDIA to be of any help, but if the Sonos is working with a ‘normal’ source, like a cable box or Satellite box, it isn’t the Sonos, but the source. 
 

But, as I suggested, if you think the issue is the Sonos, submitting that diagnostic goes a long way, once you call in, to allow the Sonos reps to see what may be happening on the Sonos, such as if it is receiving a signal at all. Or at least I assume so, I’ve never seen the contents of a diagnostic ;)