If a portable Sonos speaker misses an alarm, compare a short daytime trial on power with an unplugged trial before replacing the speaker.
Set up the test
Check the official alarm troubleshooting instructions for your exact portable model. Make a temporary daytime alarm in the right room and verify it while the speaker is powered and awake. Keep a separate reliable alarm while diagnosing this.
Interpret the result
Repeat with the speaker unplugged under the conditions where it normally fails. Check Battery Saver and whether the speaker is actually awake or powered off. If the alarm works when powered but fails after the unit shuts down, address availability rather than changing the alarm time repeatedly.
Worked example
If the kitchen speaker works in its charging location but not after a night away from power, document that difference before buying another speaker. Remove the temporary alarms when finished.
Documentation and next step
See the manufacturer’s instructions for supported settings. For a related decision, see sonos alarm grouped rooms isolation test.
