Solved :
An unknown device called "ubuntu" had added itself to my account.
To remove it I reset my password and signed out everywhere. When I logged back in the "ubuntu" device had gone and the continual resume behaviour ceased.
I noticed that a device called "ubuntu" was on my list of devices. Spotify defaulted to playing to this device on opening.
Originally I didnt pay much attention to it - I thought it must be one of many wireless devices in my home that run some version of linux. But I turned all my wireless devices off and it was still listed. I am careful with security so am somewhat puzzled about how this might have happened. Can spotify answer ? I will email them.
note : this issue has come up before see https://community.spotify.com/t5/Desktop-Windows/Ubuntu-device-is-taking-over-Spotify/m-p/4593281
addendum: I did contact spotify support (who were very good). They "secured" my account and I had to send proof of who I was (a screenshot of a paypal reciept) before being allowed to reset my password (again!). I asked exactly what the issue was and didnt get a definative reply. It is clear however that somehow a device (ubuntu) had been added to my account by someone, somehow.. the tech mentioned checking the apps given access to my account. I did this and the only non-spotify system app was one from the bbc, which I deleted, but of course its not certain that that was anything to do with it.
Transcript:
Me: ok - I already did the change password thing. and logged out everywhere. Can you tell me what happened ? is this a known issue or has spotify had a data breach?
Tech: We appreciate you’d like as much information as possible on the unauthorized activity on your account. However, in this instance, it’s not possible to determine the exact identity of the person(s) who accessed your account and how.
It's also worth checking the other apps on your account. When a third-party app tries to connect to your Spotify, we will always ask your permission before granting it access. A list of the apps you have granted access to can be found on your Apps page.
Note: Third-party apps are applications built by external developers, and not operated by Spotify.
To revoke the access of a third-party app:
1. Log in to your Apps page at https://www.spotify.com/family/overview/ .
2. Scroll down to Apps.
3. Find the app you want to remove and click REVOKE ACCESS.
I hope you find this helpful.
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