@dtarrant@kugiigi@dobey M10 problem solved! The trouble was the 'Lock when idle' setting was 5 minutes and not 3 minutes as on my N4. Took me a long while to find the config utility:
Battery Indicator / Lock when idle / After 3 minutes
Easy when you know how 🙂
I now deleted all my old accounts by deleting the corresponding apps. I then checked the accounts folder, it was empty of all files. In the meantime I had received an update. After rebooting and after reinstalling my nextcloud app, I could manage my accounts again. All working now.
Thank you once again for your assistance.
It has nothing to do with pulse-audio. It is the hybris module for pulse-audio, which is maintained by the Sailfish (Jolla) developers. For this feature to work, that module must have the support. My suggestion would be to take your issue upstream to them.