Possible solution for some of you:
I was having the same blinking issue with my 2012 mac mini. Using connectors I had and free ports on the monitors, I connected in the following way:
Mac Mini Display Port: Rocketfish Mini DisplayPort to HDMI Adapter, HDMI to HDMI cable to monitor
Mac Mini HDMI Port: Apple HDMI to DVI-D adaptor, DVI-D to DVI-D cable to monitor
The blinking had gotten really bad, happening once every 2-5 minutes. Mavericks didn't help. I decided to change up how I connected the monitors to see if that would help.
Mac Mini Display Port: Generic Mini DisplayPort to DVI-D Adapter, DVI-D to DVI-D cable to monitor
Mac Mini HDMI Port: HDMI to HDMI cable to monitor
Blinking has now stopped completely for over a week.
Hope this helps some of you out.
Actually, the blinking issue is getting worse in Mavericks once per hour.
(Mountain Lion: I didn't see this issue. Lion: I saw this issue once a day.)
I connect the 28 inch display via a Mini Display Port to Display Port cable, so unfortunatelly it's not feasible to convert Mini Display Port to DVI because of the capacity.
Hope it will be fixed soon.
The stupid work around I found is,
1. Set a hot corner to sleep the display
2. Trigger it when the display starts blinking
I have a 2012 i7 mac mini w/256GB SSD that I have been having the exact problem with as described on this site with 16GB OWC RAM installed. I am running it with dual thunderbolt displays that would flash every few minutes making the computer nearly unusable. I took out one of the memory sticks (to run on a single 8GB stick of RAM) and ALL flashing issues have resolved. I'm hoping someone smarter than me can figure out why this solves the problem....
The only solution I have found is to use the Mini DisplayPort to VGA adapter,
if you have a monitor with a VGA port on it. I have no issues with that but
if I try to use HDMI --> HDMI from my late 2012 Mac Mini, it will have a black
screen for a few seconds and this happens randomly -- perhaps a few times
I use VGA now and it is good enough but we shouldn't have to do that.
It should just work.
Intel released updated drivers for Windows 8.1 and 7 which fixed this issue
but for some reason they won't do that for Apple.
It makes no sense. Shame on Intel.
I have found the solution!!!!!!!
God, this was driving me crazy, I had just bought this brand new Mac Mini and it was tripping out!!
But here it is guys:
It's called a NVRAM and PRAM reboot, don't know why it works, and I don't really care either!! but it fixed my problem, hope Apple still releases a bug fix for this, it would save a lot of us a lot of headaches!!
I switched off my Mac mini and unplugged it
for at least 5 or 10 minutes.
I then attached an HDMI cable to it and
connected that to my monitor.
I plugged in the Mac mini and did an NVRAM
reset and there are no problems whatsoever now.
Even the audio glitches are gone! :-)
I guess I can confirm that the 10.9.2 update
Previously with 10.9.1, SMC and NVRAM resets
did nothing to solve the problem.
I've always had video glitching from the beginning on both connected monitors. I've had three different monitors connected and they all glitch. I've accepted that Apple will not admit to the problem or issue a recall. It's just the way they do business.
My suspicion is that it's a hardware race condition with the CPU and GPU sharing memory. The CPU is busy with the memory when the GPU needs it, can't get it, thus the video glitch. I see the glitching more frequently when the CPU is maxed out doing HandBrake, or I have Parallels running a VM, with other apps busy. The busyier the CPU and the more memory in use, the more frequent the glitching. YMMV.
Only Apple knows for sure what the issue is. I'm just saddened that they chose to ignore the problem. A hefty trade-in allowance on the next mini would be a nice gesture. I'm not holding my breath.
10.9.3 with P-ram restart - no flickers when just web browsing and other general stuff. As soon as I open an app like Ableton Live 9 and start playing fairly intensive arrangments (using quite a few plugins, etc.), or start watching multiple videos on the desktop, it flickers it tits off. Using a short 0.5m HDMI to HDMI to Samsung monitor.