Cinema display flashing to black on Yosemite - temporary fix
Since upgrading to Yosemite (2010 MacPro with 24" Apple LED Cinema Display) my Cinema display has been randomly going to to black for a second. My secondary display (an older LG LX40) doesn't flicker and is fine. Sometimes it happens a lot and sometimes less so. It's driving me crazy. And I've seen that other people have had the same/ similar issues.
I've tried re-installing Yosemite, PRAM and NVRAM resets etc. Nothing seems to work however I have found a temporary fix for anyone - like me - who is desperately trying to finish a job. I have been disconnecting the Cinema Display display port cable from the Mac Pro and connecting it to my 13" 2012 MacBook Pro and wait for it to display the laptop desktop. I then take it out of the MBP and put it back into the Mac Pro. This seems to clear something and stops the flickering for most of the day (but it will start up again at some point).