Set the Digital Output Audio Format setting on the TV to Dolby Digital.
EDIT: It seems that Samsung had a recent software update that is causing the issue. A temporary fix seems to be setting the Digital Output Audio Format setting to PCM.
I have the same problem and even if I select Dolby digital it does not work
Samsung released a software update for some TVs which appears to have broken some things. You may want to reach out directly to them to see when they’re going to roll out a fix.
Why they’re rolling out new software on a Friday or a weekend is beyond me,,
Tks for this info. I will certainly contact them if they have a good clientele service
Same Here. Since sone days, i have to reboot my 2019 Samsung TV (ru8009) before getting any Sound, but then IT works until I Switch TV off
It worked for me also for a while but since yesterday, even when I tried to re boot it did not work ar all.
I will try to call Samsung next week to check with them. I will let you know!
A temporary fix seems to be setting the Digital Output Audio Format setting to PCM.
Exact same problem here. “i’m using my Sonos Beam now already for a couple of years and since yesterday suddenly there is no sound coming from the Sonos.” Opened a support ticket with Sonos. They said it is a known issue and to call Samsung.
I’ve been using my Sonos beam, for a few years and experienced the same problem as of September 3. Will try the work around suggested here and contact Samgsung.
Let s keep in touch ! I will call Samsung me too
We lost the audio provided by our Sonos Beam on Friday, September1 as well. Technician sent by our cable provider could not resolve the issue. I am waiting for Sonos Customer Support to be open after the Labor Day holiday to talk to a customer service representative. I will also try to reach Samsung (we have a UHD Samsung Series 8 with an ARC-enabled HDMI connection).
It’s not the Sonos, because other soundbar brands apparently have it too. It’s a Samsung TV thing. I’ve talked to Sonos on chat, then got a case number and talked by phone today (Sept 4, 2023). They said it’s a known issue with Samsung.
Thank you. I will contact Samsung. At least the time lost this weekend trying to troubleshoot the loss of the audio led me to really research the wonderful capabilities of the Sonos Beam! We will now maximize its power to deliver msuic, podcasts and so much more!
If anyone gets a solution to this please post here. The suggestions above did not work for me. Currently both my Digital Dolby options are grayed out so I am using PCM, and sometimes that doesn’t even work and (gasp) I have to use the TV sound! 
Can relate to that I’m using the TV sound 
Our cable provider sent a technician on Sunday morning to troublleshoot the soundbar issue. He could not resolve it. He tested multuple HDMI ports in our awkward wall-mounted set-up. Then he set our TV to use the TV speaker until I could get resolution from Samsung or Sonos. To make matters worse, the cable/internet provider tested the modem and caused us to lose our network. Re-installing our modem and router failed to work. So then we had to buy a combo router/modem that is supported by our cable/internet provider. So Labor Day weekend is aptly named. I has taken days to resolve the sound issue and the subsequent networkk loss. We have reset so many devices, reinstalled devices, and sought suppoirt from so many manufacturers and service providers in the past five days! But there is a happy ending for our situation if you keep reading this post.
I called SAMSUNG and the rep said their software update would not affect our soundbar. He advised me to contact Sonos.
The Sonos rep said there is a known issue with some Samsung TVsS. But before we could address that, I of course needed to connect our Beam to our new network . The excellent Sonos tech support rep assisted me with reconnecting our Beam to our TV and connecting it to our new modem/router (new network) this morning.
We were both surprisedd when the Samsung 4K UHD TV enabled the audio to be played through the Receiver (HDMI) option! The Sonos is connected to the ARC port on the TV. The TV sound option selected is Receiver (HDMI).
I can only hope the TV and Sonos continue to maintain their successful working relationship. But who knows why the audio had failed five days ago and is now working as it should. ??? I am just happy and hope others can find a solution to this issue for their setups.
Our cable provider sent a technician on Sunday morning to troublleshoot the soundbar issue. He could not resolve it. He tested multuple HDMI ports in our awkward wall-mounted set-up. Then he set our TV to use the TV speaker until I could get resolution from Samsung or Sonos. To make matters worse, the cable/internet provider tested the modem and caused us to lose our network. Re-installing our modem and router failed to work. So then we had to buy a combo router/modem that is supported by our cable/internet provider. So Labor Day weekend is aptly named. I has taken days to resolve the sound issue and the subsequent networkk loss. We have reset so many devices, reinstalled devices, and sought suppoirt from so many manufacturers and service providers in the past five days! But there is a happy ending for our situation if you keep reading this post.
I called SAMSUNG and the rep said their software update would not affect our soundbar. He advised me to contact Sonos.
The Sonos rep said there is a known issue with some Samsung TVsS. But before we could address that, I of course needed to connect our Beam to our new network . The excellent Sonos tech support rep assisted me with reconnecting our Beam to our TV and connecting it to our new modem/router (new network) this morning.
We were both surprisedd when the Samsung 4K UHD TV enabled the audio to be played through the Receiver (HDMI) option! The Sonos is connected to the ARC port on the TV. The TV sound option selected is Receiver (HDMI).
I can only hope the TV and Sonos continue to maintain their successful working relationship. But who knows why the audio had failed five days ago and is now working as it should. ??? I am just happy and hope others can find a solution to this issue for their setups.
Changing so many things at once makes it difficult to say which change fixed it. Also, let us know if the fix remains fixed tomorrow or the next day. Others have said they get a temporary fix but it reverts.
After one week mine has fixed itself (hopefully it sticks). As of Sept 8, 2023.
Fix in for me: modify Samsung TV Audie settings to Dolby digital !! Easy as that!!
For me this works again. Could it be IT was fixed by Sonos Firmware Update?
Our SONOS soundbar is continuing to provide the sound for our Samasung with the option Receiver (HDMI) option after the reinstallation of our soundbar (and connection to our new combination router/modem) described in my long explanation 8 days ago.
I have a Samsung TV and sound stopped working all of a sudden today. Confirming that setting “Digital Output Audio Format” to PCM does fix the issue, as @GuitarSuperstar pointed out in their comment.
I have connected my beam to a Samsung connect (TV) and Sonos sound output is then output. Is the TV loudspeakers then not in function? (standard implementation)
In most TVs, when you use external speakers, the TV turns off internal speakers. Not all, which is why the Sonos process reminds you to turn off internal speakers.
