The post here is slightly confusing, as you mention the Sonos App and Airplaying the audio? Only it is the case you cannot Airplay audio from the Sonos App.
So is it the Airplay audio that’s causing the issue, which undoubtedly would be from another iOS App?… if it is, then I would simply switch the Airplay link back to your iDevice from the within the iOS Control Center when you finish playing your audio from your iOS App.
It’s not unusual for an audio app to have an option saying something like “Automatically resume music after a phone call”. (That example was from Deezer.)
If you are Airplaying then you are using an Apple device to play using an Apple technology. You are not using the Sonos app at all when you Airplay. Your issue is nothing to do with the Sonos system or app.
Ok. My terminology was wrong here. As people have rightly pointed out, I was playing Apple Music within the Sonos app so I wasn’t technically airplaying it. I actually don’t get this problem if I DO airplay to the speakers. It’s only what I last played within the Sonos app and it is always to the speaker set I last used.
Rather hilariously, my girlfriend had a meeting for the local church in the front room amd I took a call in the kitchen. The system started playing Hells bells by AC/DC in the middle of her meeting and I had no idea! Ha.
As funny as that is, and boy, is it, Sonos itself has no function to ‘resume on/after event X’ built in, so it’s likely, as previously pointed out, there is an external function occurring here.
If you can force it to happen, I would do so, and then submit a system diagnostic within 10 minutes, and call Sonos Support to discuss it.
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 phone folks, they have tools at their disposal that will allow them to give you advice specific to your Sonos system and network.
However, it’s entirely possible that they may not be able to see what’s causing the ‘start’ command, I’m not really sure, since it must be from outside Sonos. But you’ve got a better chance with them looking at hard data, to be sure.
It still sounds like a phone issue. If it’s an iPhone try disabling the hardware volume controls and lock screen controls, under the Sonos app’s Settings/App Preferences.
Your Sonos speakers, and your Sonos app, have no direct tie in to you receiving/ending a phone call. There must be some other smart home automation in place that does have access to receiving/ending a phone call, as well as Sonos. Some sort of automation in place to automatically resume playback on your Sonos speaker when a phone call has ended.
I distinctly recall the Yonomi app could do this, but others surely can as well. Smartthings? Alexa? perhaps Apple Homekit?
