No Sound: Non CEC Projector + Arcana + Arc

  • 11 November 2021
  • 5 replies


I have no sound. I followed the often shared advice here to take it to a friend's house that had a CEC tv. I took it to a friend's house, plugged it into his CEC Arc TV; opened the Sonos app and no Sonos setup was needed. The speaker played great. Thinking it was solved I took it home and set it up, but there was no sound again.

I've tried multiple configurations, including connecting the Arc HDMI directly into the projector HDMI port but nothing. My current configuration:

BenQ TH671ST Projector --> Display End of 18gps HDMI cable --> Source End of 18gps HDMI cable in Arcana --> Arc.

Arcana Port Configuration:

* HDMI In - Firestick 

* Power - Arcana Power 

* HDMI Out - Source End of 18gps HDMI 

* eArc Out - HDMI to Arc

Every time I try and setup the Sonos TV app I get the CEC Not detected error. What am I missing? Did I do something wrong/miss a step, when I hooked it up to my friend's TV?

What is not working here?

5 replies

Userlevel 7

Did you actually run the TV Setup process in the Sonos app while the Arc was connected to your friend’s TV? Did you make sure CEC was enabled on the TV?

You might try doing a factory reset of the Arcana.


When I went into the Sonos app there was no option to run the TV setup. It was already setup. I guess I can try it again....ok, perhaps the issue was that I plugged the Sonos HDMI into the TV first and because of that it didn't actually give me the option to do the TV setup, since it was already connected?


so I should try it again, don't connect it to the tv, but go into the Sonos app and follow the prompts. Also, ensure the CEC was on, witch I'm sure it was.

Userlevel 7

You can always run TV Setup under the Arc’s settings even when the Arc has already been connected to the TV.

Follow these steps:

1. Plug the Arc into power but keep the Arc disconnected from the TV.

2. Make sure CEC is enabled on the TV.

3. Run TV Setup in the Sonos app under the Arc’s Home Theater settings.

4. Connect the Arc to the TV’s HDMI ARC port when the app instructs you to.

5. The Arc will play a chime when it has been successfully connected.


I'm going to redo the setup at my friend's house today and I'll report back. Thank you!


Wanted to report that after a few TVs and tinkering it works AND IT IS AMAZING. HA HA. Dolby Atmos is no joke. Much thanks for the support here.