My MacBook Pro late 2011 has been having issues lately when I try to shut it down, it stops, then immediately starts up again. It has happened many many times now. I contacted Apple and they ran diagnostics and looked at it and they said they found nthing wrong with it (Lololol). Please help ASAP. MacBook Pro 2.5Ghz, 8GB 1333Mhz 750GB Hard drive, Nvidia GeForce GTX 6770 1024MB.