What streaming device are you using with the Arcana? If you play the film Don’t Look Up on Netflix and Black Panther on Disney+, what audio format is displayed on the Now Playing screen in the Sonos app?

Hello both say Dolby digital plus 5.1

What streaming device are you using with the Arcana? 

A 4K fire stick but for some reason the only thing I see in Dolby atmos on the app is jack ryan

Make sure you have a premium Netflix subscription, and log in to your Netflix account on a web browser and set the Playback Settings under your Profile to HIGH. Also be sure you are playing the original language track. But is it possible that Dolby Atmos isn’t supported on Netflix on your Fire TV Stick model.

Prime Video has VERY limited Atmos content. Another film on Prime Video that has Atmos audio is The Tomorrow War.

There is a good chance Dolby Atmos isn’t supported on Disney+ on your Fire TV Stick model. If you want Atmos support on all the major streaming apps, switch to an Apple TV 4K, Nvidia Shield Pro, or the latest model Roku Ultra.

Al ok thankyou

i have the highest Netflix and my fire stick is uhd 4K so thought I would get atmos somehwere

thanks for your help

It's possible that you're not seeing Dolby Atmos https://www.dolby.com/technologies/dolby-atmos/  on Netflix and Disney+ because not all content on these platforms is available in Atmos. Here are some things you can check to make sure your setup is correct for Atmos playback:

Make sure your Sonos Arc is connected to your TV via an HDMI ARC or eARC port.
Make sure your TV supports Dolby Atmos passthrough.
Make sure your TV's audio output settings are set to "External Speaker (Optical/HDMI ARC)" and not "TV Speaker."
Make sure your Netflix and Disney+ subscriptions are at the highest tier, which is required for Atmos playback.
Check the specific content you're trying to watch to make sure it's available in Atmos.

The original Fire TV 4K stick didn’t support Atmos on all streaming platforms that offered Atmos.  The 4K Max or 4K Cube will play Atmos on Netflix, Disney+, Prime, Paramount+, and Max.  Netflix and Max require the top tier subscriptions. 

Sometimes I can search for “Atmos” or “ATMOS” on a service and find content.

I have a similar question. I have arcana, sonos arc, apple tv 4K set up. I do not have any problem getting Atmos sound on Apple TV + and the sonos app confirms that it is in Atmos, However when I play Amazon Prime Atmos content (For instance Carnival Row), Arcana says that it is 5.1. I only have a problem with Amazon prime. As mention, I get Atmos sound from the other platforms. Any idea? 

Do you have a 4K TV or a 1080p TV? If 1080p, you need to set the SCALER setting on the Arcana to a 4K resolution to play Atmos audio from Prime Video.

Thanks a lot. It is a Sony full hd projector so not 4K. So are you saying that apple tv is ok to process atmos sound but for prime I need to do it, right? Because I am already getting Atmos sound from other apps. Only Amazon prime does.not process it. Thanks for clarifying.