I recently got a OWC Thunderbolt 2 Dock and am hooking my monitors into it. I have Display Port to MiniDisplay Port going from the monitor to the dock, one thunderbolt cable going from dock to Macbook Pro, and one Display Port to MiniDisplay Port going from a second monitor to the MBP.
Every so often, the monitor hooked into the dock will simply 'reset' or disconnect and then connect again. Everything I had on that monitor moves to my laptop main display and then the monitor appears again.
I have checked the lights/connections and there is no poweroff of the dock. Has anyone else experierenced this or know of a solution?
UPDATE: After switching ports with monitors, the same thing happens with the second monitor in the Dock. It also happens with HDMI to the dock (which is why I went with DisplayPort -> miniDisplayPort in the first place).
Best Answer
January 22, 2016: I had similar problem (intermittent monitor and hard disk disconnects) and called the OWC HelpDesk. The OWC technician said that problem was with the Mac Thunderbolt driver, not the Dock, and the solution is to reset PRAM/NVRAM: https://support.apple.com/en-us/HT204063 Since PRAM/NVRAM reset, the intermittent screen and disk resets have stopped. I am keeping fingers crossed.
January 30, 2016: The monitor/disk disconnects have restarted :-(
February 9, 2016: Has worked flawlessly for past 10 days, following another NVRAM reset. I wish I could understand the problem a little better, what causes it in the first place and why it goes away after NVRAM reset?