I first noticed when I shut my macbook and then heard iChat log in and load my buddy list. Then I watched it and heard the familiar cd-drive sound followed by the iChat again. Then the cd-drive, then iChat again. My macbook gets stuck in a loop when I close it. If I keep it open and tell it to sleep, the screen goes black for a second, then it comes back up and I hear iChat log in again. What could cause my macbook to be unable to sleep?