Strangely, a notification had appeared on my iPad saying that an alarm had sounded at 06:00, but no alarm was set for that time, and an alarm didn't sound then either.
Thankfully an alarm set for 06:05 went off correctly.
I hsve checked under Settings and the system is set to the correct time zone/date and time.
Diagnostic submitted under 68734651.
I have been using Alarms for years and never had this happen before. Could this issue be linked to the Alarms functional redesign in the new app? I use the system as an alarm clock for work and this needs to be reliable to be trusted.
Best answer by Ryan S
Alarms are saved in an XML file on each and every Sonos player in the household, and it's independent of the controller software running on your mobile devices. The moving of the feature in the Sonos app with 10.4 didn't change any functionality of the feature itself on the players, it was just a user interface change. The code remains the same on players, I don't think the Alarm feature has had any significant changes in years.
For now, keep an eye on things, and please let us know if you do happen to have this come up again, for this alarm or others. Sending the diagnostic right away was just the right thing to do, it helps us get any pertinent information for troubleshooting.