Beep in the night

Perhaps a time was inadvertently set to have the built-in clock alarm go off at that time.

The Date and Time system preference panel should be where you'd go to adjust the time, set the day/date, and see if the alarm or alert has been set to turn on at a specific time. That is where you'd turn off a set alert or alarm.

If that doesn't work, return and specify what you did and what did/didn't happen.

Also, you should be able to set the alarm to a time sooner than 6AM to test the sound/settings to see if that may be what has been annoying you, at a time more convenient to you for reconciling this issue.

What build/model year computer version, and

build OS X, are you having this difficulty with?

Does the computer have a startup setting for 6AM?

There is a self-test that may beep on startup if the

RAM has a problem, but that varies with the Mac:

Power On Self-Test Beep Definition - Part 2

Intel-based Mac Power On Self Test RAM error beeps

{And it may be neither of these, it could be the clock.}

Hopefully you can resolve this issue in settings.

Good luck & happy computing! 🙂

edited

a PS to the above:

After doing more reading & research, I've found it is possible for iCal or maybe iTunes to be set to turn on or emit a sound like an Alarm; this would also turn on the computer at a certain time during a 24 hour day.

So, if someone had access to your computer, (assuming automatic login or wakeup from sleep in your Admin or User account) they could have pranked you. A remote access to do this? That would be rather unlikely.

• How to use iCal/iTunes as an easy alarm clock - step by step setup (doesn't start up Mac, uses wake/sleep w/o start chime)

http://forums.macrumors.com/showthread.php?t=472229

The above post 'timed-out' before I could add what else I'd found on the topic. Maybe you can get the beeping to work to some advantage. Does the audio emit from speakers? If you can't resolve this, you may have to ask an Apple specialist or talk to a Genius. If they could only use it for a wakeup, to see how it works! LOL

Good luck & happy computing! 🙂

edited 2x

I had this same problem and tried everything...even reinstalling my operating system. Right after the daylight savings time changed I noticed it started beeping at 7am. Come to find out that I have a SkyScan atomic clock right above my computer. It's alarm was set for 6am. (I didn't know that!) when I didn't adjust the time for daylight savings it beeped at 7am. It was the clock all the time, but it sounded like it was coming from my computer. If you have one of those clocks check to see if that could be your problem. I know it's years later, but for anyone else out there that's having the same problem I had, it's worth posting.