I have been having problems with the Alarm function of my iPhone on and off for two years now. I have had both an iPhone 3G and now a 3GS. The problem is that the built-in Alarm will not always go off in the morning. It happens sporadically, but has happened with all iPhone OSes I have used, including just this morning with iOS4. It has happened with both one-time and reoccurring alarms. It has also happened with the phone set to ring and also on vibrate. Sometimes the alarm will go off once, but then if "snooze" is pressed, it will not go off again. Other times, it simply fails to off the first time.
When I wake and unlock the phone, it will then show the alarm notification. It sometimes plays the alarm sound and other times does not. This has happened when I have missed call, voicemail, and text notifications waiting, but also other times when there are no notifications waiting at all.
It appears this is a problem with the alarm not being able to wake the iPhone from sleep mode, or with it not being able to activate when there are notifications waiting.
I have tried restarting, updating, and restoring my iPhone, yet the problem still persists sporadically, regardless of any of these efforts.
Any feedback, support, or solutions for this issue would be greatly appreciated.
Thank you