Hi @Pier53, welcome to the Sonos Community!
I’m sorry to hear that you’re having issues using your Sonos Arc with your Samsung TV.
I’ve had a look around and I can see that certain Samsung TVs can fail to pass Atmos audio, however this seems to only occur for the QLED TVs and not from your TV, which looks to be an OLED from what I can find on Google.
The workaround for the above is to disable eArc within TV settings to audio to pass normally. While it’s not a step for the TV you have, it can’t hurt to try. If it doesn’t work, then I’d recommend reaching back out to Samsung for further troubleshooting.
I hope this information helps!
