System issue

Which music service(s) are you using, they all are different?

I am using Apple

I just noticed it also does that while watching TV. The volume goes up (very loud) and down

Doc,

When you say you’re using Apple, do you mean Apple TV hardware, feeding an unspecified TV?

I’m using Apple TV to feed both an LG and a Samsung, to an Arc, and I’m not seeing any fluctuations, using both Hulu and Apple TV. Can you provide more specifics.

I am using Apple subscription for music…. I do not have Apple TV

Ok, that’s useful. What speaker(s) are you playing on? What OS are these speakers running? What device is your controller on? What OS is running on that device? Have you uninstalled Apple Music from your Sonos, then reinstalled it? What kind of network are you running, and how are the Sonos connected to it? Have you unplugged all your Sonos devices from power, rebooted the router, waited two minutes, then plugged back in your Sonos devices, waited another two minutes, then tested? Have you called Sonos Support to discuss the issue? If so, what response did you get, as that might help us help you?

Since Apple Music is working well for so many people we need to discover what is going wrong with your setup. 

On the TV, what source are you watching on your TV when you get the volume changes? If you can replay the part where the volume changed, let us know if the volume changed at the same spot again.

Do,you have your Arc set up with your Sub? 

Are you using your Era or One speakers as surrounds? 

Are all Sonos using wifi or do you have some wired to Ethernet? 

I’ve suffered the same issue since the last update…

I cannot find a pattern, randomly, the music sounds insanely high just few seconds at the end of the song.

The setup is Arc - 300s - Sub3. Streaming through Amazon Music.

Making some tests, it only happens with Amazon through Sonos app, I don’t find the issue playing Spotify or AirPlay. 
It usually happens in HD tracks -last 12-8 s- or in Ultra HD -last 6-4 s- (but not in all of them) never in Atmos.

After two calls to support, check that the issue is not happening in the Amazon Music itself, just in Sonos one, uninstall Sonos app in all devices, reboot all the speakers, reinstall the app, reattach the Amazon service to the Sonos app, send diagnostics and invest one hour… I reach the level 2!

Level 2 asked me some more questions, another diagnostic and forward the case to engineering. 
Ill keep you updated.

Given that no one else seems to be reporting this, it certainly seems like a local issue of some type…but I can’t come up with a single thought as to why it’s happening at all, much less only on Amazon Music tracks. And given that Sonos uses the same ‘player’ software across all music streams, just pointing to different locations to get each, it certainly seems like it’s harder than average to point the metaphorical finger at Sonos, too. I’ll be interested in what level 2 support can find out. The only thing I can think of is some sort of interruption/data corruption in the stream you’re getting from Amazon…but that just really doesn’t track with ‘end of the songs’ much, either. 

Keep us posted, please. 

Oh, one thing to note (although it may not be relevant) is the server that Sonos contacts isn’t the same one that any other device (like Amazon Music apps) contact. Likely for tracking purposes. As to whether the data is the same or not, you’d have to speak with Amazon about, I have no idea if it’s different data sets or just a different port.