Hi @Sri662 

Welcome to the Sonos Community! And, apologies for the delay.

Are you playing stereo music? If so, it is expected that you would not hear anything from the centre channel of the Arc - Arc will play the stereo feed through it’s left and right speakers, then repeat those channels on the surrounds if the settings ask for it.

If you are playing Atmos music from Amazon Unlimited or Apple Music, however, that would be a different matter - please let me know if this is the case. Your mention of Atmos over AirPlay makes me think you might be playing Atmos music.

While I am on the subject, although Apple recently added support for Atmos to AirPlay, that is only for when the receiving device is also manufactured by Apple - although we’d be interested in supporting Atmos over AirPlay, it is not currently an option for us.

I just found your case and, reading the notes, I believe the agent was suggesting a mesh network simply as a better alternative to using the extender that you already have, but was not (or so I hope) suggesting this as a proposed solution to the issues you were reporting.

I have heard some other reports about surround mixes on Arc Ultra, though this is the first that I know of that might be referencing Atmos music playback. We are investigating these with priority.

I hope this helps.

I really appreciate the reply. 

Here is an example and test I’d suggest to surface the problem. 

I am playing atmos enabled songs on Apple Music service on Sonos App. I have 2 configurations in different rooms and hear the same issue in both

Configuration 1: Arc ultra + Sub 4 + Era 300 as surrounds

Configuration 2: Arc Ultra + Sub 4 + Sonos one SL as surrounds

The song I am playing is “Jo Tum Mere Ho” by Anuv Jain. Play it from 50 sec mark to 2 min 30 secs and hear for yourself how oddly the sound plays with surrounds spiking in volume and arc going low on the vocals at multiple points

This issue did not exist when I had Arc, Sub 3 and Era 300 and does not exist for my other room where I have Beam Gen 2, Sub mini and Sonos One SL as surrounds.

When connected with HDMI to TV, the content seems to be playing fine but when playing music over the app wirelessly, doesn’t work well

This issue is not just with one song but a few ones I played that are Dolby atmos enabled.

Hoping you will do the test and let me know what I need to do to fix it. I was considering returning both Ultras but decided to keep them hoping there would be a fix coming up.

Thanks again for hearing me out.

Hi ​@Sri662 

Thanks for naming a track to test. I tested it on my Arc Ultra and heard no issue with the volume (either by number or by perception), but my surrounds are not currently working so I am not convinced that this is a fair comparison - I’ll give that track another test once I resolve the issue I am having and let you know how I got on.

In the meantime, can you please try removing the Sub and Surrounds from one of your Arc Ultras and testing playback on the Ultra with that configuration? Please let me know if the behaviour is the same or different, and in either case, please bond the Sub and Surrounds back to the Arc Ultra and test once more. Please submit a support diagnostic after all the testing if the issue has not been resolved and let me know here when you have done so, but please don’t share the number given.

I hope this helps.

Thank you Corry

i did the test with disconnecting the sub and surrounds as well as connecting them back. I see the same issue with Arc ultra alone as well

Particularly listen to the track at 1:01, 1:15 (volume goes up in some channels), 2:02 (vocals go down) and 2:43 (vocals go back up)

Let me know if you don’t notice anything odd

here is another song “Senorita” to listen to from 2:15 - 2:35 - same issue but more evident with surrounds (era 300) and Sub 4 vs Arc ultra alone 

pls read this link if you can - similar issues

https://www.reddit.com/r/sonos/comments/1glg4tu/arc_ultra_surround_not_right/

I submitted diagnostic

Hi ​@Sri662 

Thank you for your patience - I now have my surrounds working (a regional issue as I have a unit in the UK that was destined for the USA). Thanks for testing with Arc Ultra only too.

I have no idea what Mr. Jain is singing about, but as the first Atmos music I have listed to, he sounds fantastic!

I do now hear what you mean about those specific moments in the track, and it sounds to me entirely intentional - I believe he is harmonising with himself (he has recorded his own backing vocals) and they seem to kick in and drop out at the times you specified, so I think the changes in volume that you are reporting is just the way the Atmos recording was mixed, with the lead vocals being at the front, and the backing vocals coming from the surrounds.

I tried Senorita too, but couldn’t really make out a difference (though I do not have Era 300s and you did mention that you hear it more clearly on those).

We are all long used to stereo music, and I believe what you are hearing is somewhat akin to bands like Queen playing with stereo imaging in the past (in the 70’s or round about there) - something that you no longer hear in today’s music. Though we do get instruments only on one side (I’m thinking rhythm guitar versus lead guitar on Metallica tracks here), you don’t really get sweeps or jumps from one side to the other any more. I suspect that in a decade or two (or sooner) we’ll see a similar reduction in this kind of mixing on Atmos tracks, but I do think this is intentional on this particular track.

I will mention these tracks to some colleagues for them to try as well, but if they come to the same conclusion as me, I think this story may well end here.

I hope this helps.