I have found recently an issue with my #X Compact. I have set an alarm e.g. 5:30. Then I have set Do Not Disturb on until the alarm happens. But for some reason the alarm starts at 5:45, 15 minutes later than it has been set. I'm sure that it hasn't ring at the correct time, 5:30. I'm also sure that I haven't pressed Snooze button. And the snooze time is 10 minutes. Even if I have had set snooze, the time of real alarm doesn't match. This problem has happened a few times during last week. What might be the reason for it?