My first post here, hope this is the right place. Every midnight the computer starts making a beep beep and so on until it starts beeping constantly unit it stops about a minute later, then it does it again at exactly 12:10 am. It does this when off or on/standby mode with speakers off. It is a sony Vaio about 10 years old with Windows xp. Any ideas? Only way to stop the sound is to unplug all electrical plugins.