If the tv screen went black, might it be the tv at fault rather than the Arc? Does the Arc play music ok? Does the tv work ok if you disconnect the Arc and use it standalone?

Hi Thanks for coming back to me so promptly. I’ve not had the chance to check that but will do. Would the ‘lounge’ system as I’ve called it disappear from the app though if it was the TV. It does come back during the moments it’s stable.

What color is the flashing LED?  
Click the link to diagnose and let us know.

https://support.sonos.com/s/article/226?language=en_US

Hi It flashes white for the second or two the TV screen is blank.

As per the link your Arc appears to be booting up. Check the power connection on both ends. Let us know the results. Also, if using a power strip try plugging the Arc directly into a wall outlet.

Hi

Both ends checked and all secure. Tried out of the power strip and still the same.

What happens when the TV is just left off or in standby and you’re just playing music audio to the Arc from the Sonos App? Is it still rebooting and stopping playing in that situation?

No issue at all with just music

I would see what the TV does next. Remove the Arc’s HDMI cable from the back of the TV and power on the TV and see if it runs okay on its own internal speakers. If it does, then maybe try a different HDMI cable between the Arc & TV and then see what happens in that case. 

Thanks will do

Note you ‘may’ have to toggle off HDMI-CEC in the TV settings when running the TV on its internal speakers and don’t forget to switch it back on when you later reconnect the Arc.

One more question…what brand/model is your TV?

Panasonic 65HZ2000

Have you checked your menu for updates to your Panasonic? Also I would contact Panasonic tech support and discuss the issue with them. It may be a known issue for which Panasonic my have a fix. Especially so since everything was working fine for a year using the same setup.

Will do

Hi again

I know you’ve gotten a lot of “do this and try this”. My apologies if nothing has helped to resolve the issue.

To recap …suggestions that have been given are to:

Check power connections

Check and/or swap out the HDMI cable

Check TV menu settings 

Call Panasonic tech support

All good suggestions. However there’s one more…

Reproduce the issue and immediately submit a Diagnostic report to Sonos and post the reference  number in your next post. Call Sonos tech support to discuss the findings. I doubt it but it could be something wrong with the Arc. Click the link for instructions on how to submit.

However, my gut feeling is that there’s something going on either with the HDMI cable and/or the Panasonic is somehow sending a signal via CEC telling the Arc to reboot???

https://support.sonos.com/s/article/141?language=en_US

Hi Have been away for a few days so powered everything off whilst away. Upon return no issues at all yesterday…so looks like it’s now sorted but strange as not really done anything but good news nonetheless.

Spoke too soon, just happened again. Will submit report.

Diagnostic report 110646644 submitted.

And again…new report 2077527545

Hi @Gibsy 

Welcome to the Sonos Community!

Your Arc appears to be rebooting because it detects a change in how it’s connecting to the network. It’s strange that the TV picture goes black, but presumably something to do with the TV detecting the change in status of the Arc.

Regarding connecting to your network, Sky Q boxes (which I presume you have) can cause many problems with Sonos as they do not allow the types of communication that Sonos depends on. I highly recommend that you permanently connect one of your Sonos products to the router with an ethernet cable. Any speaker will do - just don’t use the Lounge surrounds or Sub. Within a minute or two, the entire Sonos system (Moves and Roams excluded) will connect to it’s own private WiFi broadcasted by the wired Sonos unit.

This will make your Sonos system much more stable.

I also recommend you reboot your router by removing power for at least 30 seconds, and repeat this several times a year - let’s say quarterly.

I hope this helps.

Hi 

Thanks for the info. 
You are correct I have Sky Q but everything has been stable for 12 months or so.. I have a boost via Ethernet already…is that sufficient? Have you managed to look at the diagnostics? Thanks

Hi @Gibsy 

I did indeed look at the diagnostics, and no Boost was present - this is likely the cause of the problem.

Please ensure the Boost has power and is still connected via ethernet. If it has power, please reboot it. If the Boost appears to be faulty, wiring a speaker instead will suffice.

Hi

Checked the ‘Boost’ and there was no activity on the ports at either end - Boost and Router. Reset it and activity is showing and ‘Boost’ is now showing again in the system. Will now monitor and report back.