I’m mildly confused. Did you remove the X-box and the Virgin Cable box, or did you not?

Have you checked all four devices ( the TV, the X-Box, the Sonos,  and the Virgin)? Have you unplugged all four devices, temporarily, from power? Which ‘setup’ are you talking about, what error/failure code are you getting, on which device? What device are you using to try this setup process for Sonos, and which OS is it using? 

Have you submitted a system diagnostic within 10 minutes of experiencing this problem, and called Sonos Support to discuss it? Don’t post the resulting diagnostic number here, they get sensitive about GDPR.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

Hi,

Many thanks for your reply and apologies for my vague description of the issue, I’m a bit new to this. I’ll try to explain a little more clearly ( I contacted Sonos support who explained some steps to follow after submitting a system diagnostic. This was done via a live chat and I have now been given a case number and phone number to contact Sonos in the UK after the live chat efforts failed to resolve the issue). 

The “setup” I referred to was via the Sonos app on iOS. Within the app I was working with the Arc Ultra and it’s “TV Setup” which is where I receive the error messages. I can however view and adjust all of the Arc settings and play from all sources……despite the error messages. 

There are 3 devices connected to the LG G5. 

HDMI 1…no connection 

HDMI 2….Sonos Arc Ultra

HDMI 3…Cable box (Virgin Media)

HDMI 4…XBox One S

In chatting to Sonos support, I removed all HDMI connections except the Arc. Also unplugged everything and tried the “TV Setup” via the iOS app again. This time the error had changed from, “A device is interfering with the HDMI connection. Disconnect any other home theater products, then try again” to “Cannot find eARC” ( I can’t remember the exact message! ). Have tried a number of times since after checking a variety of settings on the TV but to no avail so far. 
 

I’ll make the phone call to Sonos today but would again appreciate your suggestions on where I may be going wrong. 
Thanks again. 
 

Seems (!) like you’re doing all the right things. I’d still want to check the TV and Sonos for firmware updates. Then I’d want to confirm the HDMI cable is the correct version, and that the iOS device is running the correct iOS version, and the controller app is up to date. And that there aren’t any work profiles, VPNs, virus protection apps, or other port blocking applications keeping the Arc from communicating properly. 

But it’s harder for us in the public to diagnose things, we don’t have that access to the hard data in the diagnostic that Sonos folks do. There’s a lot of ‘well , 99% of people have this issue when they post about it’, but I suspect we aren’t always correct. 

Keep us posted, if you’d be so kind, in what the folks at Sonos say. 

Hi, thanks again for your help. 
 

Will contact Sonos later this morning. 
 

TV software, Arc Ultra, IOS are all updated to latest versions and Arc to TV is using the HDMI cable supplied with the Arc. 
 

I cannot control the volume of the Arc with my LG magic remote either, despite following the steps to do this and receiving confirmation that it’s completed. I am only able to control the volume via the app on my phone or by the physical controls on the Arc….is this issue likely to be related?

Thanks again. 

Related, I suspect. The volume commands comes from the TV set, sent across the CEC (HDMI-ARC) connection, via the HDMI cable. It doesn’t occur on the Sonos directly, via the controller (normally). If you’re having trouble getting the TV to recognize the ARC connection with the speaker, that would be why the volume isn’t being sent. 

Oh, one more thing before I go to sleep. Make sure you’ve rebooted both the TV and the Sonos, just in case. You would do this by unplugging them from power for at least two minutes. Don’t just ‘turn them off’ using a remote, that doesn’t really turn them off, it just puts them in ‘sleep’ mode, not forcing a reload of their respective firmware. 

Thank you

You are not trying to play DTS formats by chance are you?

LG on G5 went cheapskate way like Sonos has by not utilizing all DTS formats.  It is lazy and very frustrating by LG and Sonos.

Thanks for suggestion. No, not trying to play DTS.