Bought a new 15 inch rMBP last November. Running the latest version of Yosemite with all necessary updates. Also installed FCPX, Logic and some other Mac apps. About 2 weeks ago I turned on my computer and noticed after several minutes the menu bar clock was frozen in time. It was about 5 minutes behind. Clicked on the menu bar clock and the clock and several icons to the left disappeared. Rebooted and the same problem. Repaired all disk permissions, flashed the PRAM several times, ran Apple diagnostics using the internet and fiddled with time/date settings in System settings and still the same problem. One additional problem is that my external hard drive gets disconnected if I slightly "bump" the Apple thunderbolt cable. Took it in to an Apple store. They ran the hardware diagnostics tests. No problems. Had them wipe the computer clean and reinstall Yosemite. The clock worked. No problems. Took it home and did a reinstall of all data from an external hard drive using Time Machine. Sure enough the menu bar clock problem reappeared.....aggghhhh! I wiped the computer clean again and reinstalled Yosemite. No disappearing icons from the menu bar and the clock keeps time. New problem....Finder displays both English titles and Japanese titles mixed in the same left hand column. I have run Bitdefender and Sophos antivirus/malware check software on both internal data and external HD data. Nothing found. What the heck is going on with my machine? Took it back to Apple again. They will replace the logic board next week. I have been using Macs for over ten years now. I have a feature length documentary (over 5 hours of footage from several countries) to edit down to 45 minutes. I am losing confidence in this machine. If the logic board doesn't fix this ghost in the machine what should I do? Very perplexed!