HDMI-eARC must be ON.

Have you definitely connected it to your HDMI-eARC port?

On your TV, under Settings - Sound, does it show the Sonos Arc there as being the output receiver?

What colour is the light on the front of the Arc?

I think it's HDMI 3 which is eARC, this port MUST be used for your SONOS Arc.

Try watching this video. Samsung TV HDMI ARC not working - simple solution

I recommend disconnecting all HDMI cables from the TV, make sure that the TV’s Anynet is enabled, and power down the TV and ARC for at least two minutes. Next, power-up the TV and ARC and allow them to boot. Finally, connect ARC to the TV’s HDMI-eARC port and allow them to exchange their capabilities. Now you can connect other devices to the TV, if any. I would test the TV and ARC operation before connecting other devices because the other devices might attempt to take control. AppleTV and some games can attempt to rule the land. There are workarounds if this is the situation.

HDMI-eARC works on or off. I have tried both.

Definitely connected to the eARC port.

Sound Output Settings shows: TV Speaker, Sonos Arc(HDMI), Receiver(Optical), and Bluetooth Speaker List.

Light on Arc is white.

With HDMI-eARC Mode set to Auto, it continues to switch between TV Speakers with sound and Sonos Arc with no sound.

Thanks, I’ve tried this multiple times. It works for a couple hours, then no sound out of the Sonos Arc.

​@Silverway780 

Are you using the HDMI cable that came with the Arc (i.e. a High Speed HDMI cable) rather than a legacy one from a previous set-up? By the sounds of it, the Arc worked with the Sony but not with the Samsung. I would still ensure you’re using a high speed HDMI cable.

I’ve purchased multiple HDMI cables all ARC rated. I need a 10-15’ cable. I tried reusing the one that I used with my Sony and it briefly worked.

I’m at a loss too - but here’s what A.I. has to say on your specific case:

Suggested Fixes (Prioritised)

1. Turn ON eARC in the Samsung TV:

   • Settings → Sound → Expert Settings → HDMI eARC Mode → Auto or On

   • Sonos Arc requires eARC for lossless Dolby Atmos over TrueHD.

   • Disabling eARC can cause fallbacks to compressed formats or PCM stereo.

2. Use a Certified Ultra High Speed HDMI cable (HDMI 2.1):

   • At 10–15 feet, a cheap or uncertified cable may appear to work temporarily but degrade under high-bandwidth audio use.

   • Use one with the official “Ultra High Speed” HDMI Certification Label, ideally from brands like Zeskit, Cable Matters, or Monoprice.

3. Enable Anynet+ (HDMI-CEC):

   • This must be ON for ARC/eARC to work properly.

   • Path: Settings → General → External Device Manager → Anynet+ (HDMI-CEC) → ON

4. TV Audio Output Settings:

   • Set Digital Output Audio Format to Auto (not PCM)

   • Set Dolby Atmos Compatibility to ON

5. Try HDMI port 3 (eARC):

   • Make sure the Sonos Arc is connected to HDMI 3, which is the eARC port on the S95D.

6. Avoid External HDMI Switches or Sound Interruption Devices

   • If using any intermediary HDMI device (like an HDMI switch or splitter), remove it for testing.

ALSO:

• Update TV firmware to the latest version via Samsung’s Support settings or USB download.

Nothing is working. Only thing I can think of is to try a new Sonos sound bar. I’m about to give up.