@peterbault - your setup is an interesting one as you have one that works and one that does not! I am assuming they both connect to your MESH, and that they are both running the same version of software  from Sonos. What's making my head hurt, is I cannot work out what is different between your setups. 

There has to be a difference somewhere but just can't work out what it would be!

The only differences that come to mind for me is I have CEC disabled on all source devices on my issue-free system. No apple tv

im really curious if I would get the issue if I used an Apple TV on my non-issue system 

Yes my system is HDMI 2.1 (LG c1) and I have the issue

Not me. Just ISP provided gateway/router unit

I am also (for some mad reason) really curious about the position of your speakers in both the non working room and the working room.

i.e. do you have the sub very close to the ARC in non-working system and further away in the working one? (The mad thoughts here is some strange interference between the propriety ‘ad-hoc’ network that is getting created). Although, that would not explain why this happens (to most at least) when moving between sources. 

My sub is within 2’ of the left edge of my arc. Not sure where the wireless radios are within the units but interesting thought

Is the sub further away in the working room?

(Mine is less than 1 foot away for reference)

EDIT - Sorry, that was meant for Peter!  To busy not reading the names when responding!!

Ya sorry for jumping in there. I’m interested in Peter’s response to your question too because of his 2 systems. Just thought I’d pipe in and start building a body of data for that hypothesis

No stress! I naturally assumed you were Peter responding!! :-) 

system with no issues (LG CX):

this is in my office/game room, its a relatively small room. sub is behind my couch, maybe about 6 feet from the arc. rears are sort of behind the couch too but further to the side outside the couch, maybe 7 feet from the arc? the funny thing is if there were interference issues I would expect them in this room because I have a ton of wireless things in there its also where the router lives. the router is maybe like 2 feet away from the arc in this room

system with the issue (Sony A9G)

I have a sectional couch and have a sub on each end. 1 sub is maybe 6-7 feet away from the Arc. the other sub is probably more like 9-10 feet away from the arc. Rears are even further out its probably like 12-14 feet from he arc. I have a Orbi satellite in this room as well but its pretty far away from the Arc, its like 20 feet or so its practically in the dining room.

Thanks Peter for the detail. OK - so that does not sound like a problem. Mine is very close, and yours is 6 feet away. 

For my next network test (probably my final) I noticed that my NetGear Orbi router kept changing IP address. Like it’s requesting a new one from my router (which is the DHCP server) so that did not seem great. I have earlier assigned all three Orbis to a static address to see if that rules it out.

@peterbault - can I be a real pain and ask a favour?

Can you please play movies on your working system and your non-working system, and whilst they are playing can you please send me a screenshot of the matrix for each?

Ideally, it would be great if you could initially send the matrix images whilst both are working, and then one after the system breaks at some point. 

For context, when I see the problem my matrix looks different to when I am not getting the drop outs. For example, I have been watching films and flicking around for 4 hours + and no issues. Matrix looks like the below:

When I have issues, typically, the matrix looks a lot more populated with grey. (NOTE: ignore the fact there is less speakers, just quickly sourcing examples):

I am just wondering whether yours looks the same when comparing working and non-working systems?

@peterbault - can I be a real pain and ask a favour?

Can you please play movies on your working system and your non-working system, and whilst they are playing can you please send me a screenshot of the matrix for each?

Ideally, it would be great if you could initially send the matrix images whilst both are working, and then one after the system breaks at some point. 

For context, when I see the problem my matrix looks different to when I am not getting the drop outs. For example, I have been watching films and flicking around for 4 hours + and no issues. Matrix looks like the below:

 

When I have issues, typically, the matrix looks a lot more populated with grey. (NOTE: ignore the fact there is less speakers, just quickly sourcing examples):

 

I am just wondering whether yours looks the same when comparing working and non-working systems?

Sure It may be awhile though. Wife is watching her garbage right now 

No stress, in fact, it may not be worth it as guess what? Yes, the speakers dropped!

@Ken_Griffiths - I did however take your advise and monitor the support pages.

When the system was working yesterday/tonight, this was one of the speakers (RR). You can see it operating on channel 5200. 

After 4 hours of play tonight (and an eventual break) I quickly had another look when it stopped working. Now you can see that the “Operating on channel” has moved to 5300. (Home channel remains the same).

After I reboot the ARC (power off, 10 seconds, power up) then the channel has moved back to 5200 and all sound has been restored.

I am not sure what this means, whether the 5Ghz Ad-Hoc channel is meant to change or what. But there has been some movement.

Ken or anyone think this is a problem or somehow linked? 

No stress, in fact, it may not be worth it as guess what? Yes, the speakers dropped!

@Ken_Griffiths - I did however take your advise and monitor the support pages.

When the system was working yesterday/tonight, this was one of the speakers (RR). You can see it operating on channel 5200. 

After 4 hours of play tonight (and an eventual break) I quickly had another look when it stopped working. Now you can see that the “Operating on channel” has moved to 5300. (Home channel remains the same).

After I reboot the ARC (power off, 10 seconds, power up) then the channel has moved back to 5200 and all sound has been restored.

I am not sure what this means, whether the 5Ghz Ad-Hoc channel is meant to change or what. But there has been some movement.

Ken or anyone think this is a problem or somehow linked? 

Interesting indeed. Perhaps something causes the system to think it needs to switch channels but the arc ends up stuck on the old channel while the other speakers are on a new channel? 

Maybe.

In the end, that channel moved from 40 to 60. Although this is one test, it seems to like operating on 40 in working operation and also after a reboot. When it moved (on this occasion) it correlates with the sound drop. 

My own network only supports 36 to 48. But, as I understand, this is an adhoc channel created by Sonos HT so it does not have rely on my network capability.

I guess a way to prove this is affected users take a snapshot of their information whilst working, and then go back and check if the Operating on channel frequency has moved when the sound drops, Not sure what it all means, but if we find a correlation between affected users it might be a step forward?

Maybe.

In the end, that channel moved from 40 to 60. Although this is one test, it seems to like operating on 40 in working operation and also after a reboot. When it moved (on this occasion) it correlates with the sound drop. 

My own network only supports 36 to 48. But, as I understand, this is an adhoc channel created by Sonos HT so it does not have rely on my network capability.

I guess a way to prove this is affected users take a snapshot of their information whilst working, and then go back and check if the Operating on channel frequency has moved when the sound drops, Not sure what it all means, but if we find a correlation between affected users it might be a step forward?

 

When your system was broken just now did you happen to view that same status screen for your arc? Was the HT channel 5200 or 5300?

Doubt this is wireless related at all. I’ve had sync and drop issues; 100% of my system is wired. Arc, 2xOne’s, Sub - all ethernet connected. All wireless disabled on all Sonos speakers. The only wireless Sonos in my setup is my Roam and my Move, which don’t use SonosNet (they connect to your regular AP).

Weird. My living room system is showing 5ghz for the home theater and bonded speakers while my office system shows 2.4ghz channels for everything. Home theater channel is reporting as 0 on my office system 

 Just to confirm. You have wireless turned off in the controller app on all your speakers? 

I did not catch a screenshot unfortunately, but I have observed that (when playing a movie) the Operating on channel never moves from 2412 - which is a 2.4Ghz channel 1 and where my Sonos Net is configured for. 

Mode: INFRA (sonosnet)Operating on channel 2412Home channel is 2412

I will check this again and make sure I crab a screenshot.  However, at the moment the ARC seems to sit on the SonosNET channel 1, it creates a 5Ghz ad-hoc network when playing HT content, and I have seen that frequency move from 5200 to 5300 - at which point it seems to correlate to a sound break. 

Mode: INFRA (sonosnet)Operating on channel 2412Home channel is 2412

When you view that status screen for your arc you should see operating channel which would be 2.4ghz channel and HT channel which would be the 5ghz ad hoc network for the bonded speakers. I wonder if when this issue occurs the 5ghz channel for the arc and the bonded speakers are no longer the same 

And which system (living room or office) is the one that is playing up?

oh I think my office system is showing 0 for HT channel is because I’m not currently playing anything in there 

Sorry see my previous post. I think this is working as expected for a system not in use at the time