I have a Surface Pro 3 with a Microsoft Dock and 2 Dell U24 monitors in DisplayPort 1.2 mode. I hooked everything up and it all worked fine, I've been using it for about a week. When I came in this morning the screens were black and the monitors weren't recognized by the Surface. I did the Windows Update dance, unplugged and replugged everything within 10 feet of my desk, rebooted a dozen or so times both in and out of the dock. Now the Surface recognizes both monitors but when I try to use the 3rd monitor I receive an error saying "The display settings could not be saved." What changed?