Thunderbolt Display Flickering Epidemic - Extensive Testing

I've had this problem with 2 Thunderbolt displays - both not new, but both plugged into a new Mac Pro (MacPro6,1). I've been kicking it around for a while; the second display seemed to work much better but is now "showing signs" of flickering (blanking off for 2-3 seconds several times per day).

Reason I'm adding this: it appears that somewhere this is being seen - see Apple Thunderbolt Display: Image on display intermittently goes dark, USB devices not available after waking from sleep … The date on this seems indicate that it's a new article (3 March 2015) so perhaps the problem has bubbled up to some extent.

And, yes, there's nothing particularly helpful in this, but maybe it means they are getting around to acknowledging the issue...

I called apple support with several issues. They arranged to call me back and didn't. I called escalated it to a call center supervisor and he said someone would call, they did. But then the original support person who spent several hours on the phone became available and was going to call me. They didn't. I did get several emails back and forth arranging times and now nothing. Silence. I am frustrated with this. I first called because I suspected a hack or something taking photos on my mac pro (late 2013), but that's not it. I can run for a week offline and still randomly it 'blinks'. It's creepy. And I"m about out of warrantee on this monitor. Anyway, I have this issue too like so many others. I've run all the firmware updates and confirmed and redone them. I've stripped my machine bare, reinstalled the os. I have NOT tried getting Apple to replace the cable on the monitor. But looks like some people are having success with that. I'm going to by an external cable and see if that works. If that is the solution, then apple got screwed by whomever made those parts for them and should issue replacements to anyone who purchased a thunderbolt display. They did that on the iPhone power supplies a few years ago. That was honorable. They should do it now for this problem.

So I got an external thunderbolt cable (the 6' one) and have been using it for about a week now and (crossing fingers) the display hasn't flickered out on me once. So...great. Maybe it is the built-in thunderbolt cable that is the problem, and it's not a software issue.

But, I call the local Apple store and they say call Apple care, which I do. I ask how long they would need my monitor to diagnose it and replace any defective parts. Up to a week. WAT! Is there a loaner monitor avaiable? no. we don't do that. Hrmmm. So I could just buy a new one and return it after mine is fixed, but that is really shady. Nice play here Apple -- something is clearly wrong with the hardware, and you know it, since many others are reporting it, but the store and Apple care act like this is the first they've heard of the problem? Also, what's with the talk to the store, then apple care, then the store, then apple care routine?

Really lame. So my advice to anyone else experiencing this is to try an external cable and see if it helps. Yes, it's another $40 to Apple but you can always just return the cable after a week. Or get stuck using it, like me, because you can't give up your monitor for a week.

C'mon Apple -- like another poster here said, you obviously know there's a defective part somewhere, or a high chance for one, so why not just admit it and help us get it fixed?

Same issue here with a MAC PRO (Late 2013 - OS X Yosemite 10.10.3). Screen flickering, same behaviour as described in previous posts and unfortunately the display is 1 month past the warranty period of 1 year.

The workaround with the Thunderbolt Cable works fine but is not really what I want. A real solution by Apple IS the solution!

Strange but on my Macbook Pro (Late 2013 - OS X Yosemite 10.10.3) the flickering doesn't occur.

A firmware issue with the Thunderbolt ports/busses on the MAC PRO?

Really a shame Apple is not admitting there's an issue!!!!!

Done the same fixes, still happens on my MacBook Pro (Late 2011) running Yosemite.

Just looked to contact Support online, which the store suggested a while back. I'm out of warranty. This is a manufacturing flaw, I should not have to pay for service. So instead of talking to them I will share my story here too. I will continue to try to find work-arounds and share any successes.

I have had the same problem. I bought another Apple cable to circumvent the display connection. No. Drove across town, lugged the screen to Apple store they kept it a few days and said it tested fine, maybe I have a power supply problem. Bought a second CyberPower back-up Battery/surge protector, put it on a different circuit in the house plugged it in alone there. I get an alert from the CyberPower if the power fluctuates, it has not. Now getting worse. Updated to Yosemite. No.

My MacBook Pro can run two 8TB RAID Thunderbolt drives and a USB2 portable drive with no power issues, so it is not the computer. I was choosing which I want, the drives or my monitor (which is insane for the price I paid for the monitor). Now it doesn't matter, screen cuts in and out, suddenly black, sometime a flicker, often longer. Sometimes it comes back when the cable is disconnected, more often now it does not. Happens whether it has just started up and everything is cool and after it's run a while and everything is warmed up. There are no distortions or other weirdness you usually get with a video card going bad.

I've stuck with Mac through thick and thin since my first one: A Powerbook Pro 100 purchased in 1991. I know these computers. I expect more. With the advent of Adobe Creative Cloud a switch to my PC laptop can happen overnight. I'm just about ready.

MacBook Pro (13-inch, Late 2011), 2.8 GHz Intel Core i7, 8 GB 1333 MHz DDR3, Intel HD Graphics 3000 512 MB

Yosemite 10.10.3 (14D136), all software and firmware updates have been run

I just want to add to the comments and replies. I have a MacBook Air that is complete up to date with the "firmware" updates with the proper OS update. I have a TB display at work and at home. The one at home works fine (for now) and the one at work continues to have the same issues discussed in this and multiple other posts. This has to be an Apple Quality issue and it must relate to the production of this unit. It is a shame that Apple can continue to take money for a defective product. I appreciate the "workaround" provided here. I am also just beyond my warranty period.

Well, I have had the replacement cable and separate power source for a few weeks now (since May 6 entry here). The problem has not gone away. It looks like something that would trigger a seizure. At times it finishes flickering and goes dark for several minutes. It drops linked Thunderbolt drives so I must choose which I need most, thank goodness I have the laptop screen. I'm shooting video of it, when I get a chance I'll post it on YouTube and post a link here.

Man, I wish I had checked the forums before I shelled out $1,000 TODAY. The display started flickering after an hour, go black and stay black. I unplug, replug, and it's fine for a few minutes then the same thing all over again. Firmware is updated. Do I have to traipse this behemoth back the the store?

Hi! I suffered with this problem for months and finally figured out a solution! And I haven't updated the firmware like Apple suggested for fear of creating a thousand dollar paperweight like others have stated on here. I haven't had any problems with my display flickering or going black since I did the following:

I only use my display at home of course. I use the power cord that came with my macbook pro instead of the one included with the display cord. Then I plug only the thunderbolt plug from the display cord into the thunderbolt port on my macbook pro. The whole problem seemed to be the laptop power plug on the display's cord. See if that helps!

Wanted to add that I bought my macbook pro and thunderbolt display around April 2011.

Update: it got worse. (BTW - I had tried the cord switch to no avail.) It has finally died. A flicker at start up then black within seconds. It is in the shop for at least a new LCD, possibly more. Sigh.

The Thunderbolt Firmware Update that I HAVEN'T installed is 1.2. In most cases I've read about online installing that update finishes killing the display.

To all who don't have brand new Thunderbolt displays and/or brand new laptops, and who have Yosemite, but have not installed Thunderbolt firmware update 1.2:

(I have version 1.18 for the thunderbolt, running 10.10.3 on a mbp retina 13-inch, late 2012)

I had the same flickering issue as everyone else, except that it did not completely die at some point, as I think I saw mentioned in some posts. What seems to have solved the issue is cleaning off the thunderbolt cable that connects the laptop. I just used a microfiber cloth (if you regularly wear eyeglasses, you may be in luck) and wiped off some white-ish, translucent deposits that I found on the "male" bit of the cable, and it seems to have worked. My thunderbolt display now works with my laptop again, even while the laptop is closed.

Two more trips after they replaced the screen and logic board. At this point everything except the glass and base has been replaced. Still happened, brought in computer with monitor, again. Now they can't prove, but speculate, my computer logic board is dying (although there are no other symptoms and obviously the display did have problems, the parts weren't replaced for no reason). I can't afford to be computer-less so I broke down and bought a Mac Pro tower. I am attempting to write this between flickers, and blackouts. it has taken about 30 minutes and two restarts. I will be back to the Apple store with tower and monitor ASAP.

I've hoped I would get a happy ending and could say Apple came through for me, they always have in the past. Not this time. If you are thinking of buying one of these monitors, run, don't walk, out of the Apple store, get anything BUT an Apple Thunderbolt monitor. There are too many stories like this, too expensive of a gamble. There are affordable quality alternatives.

Add me to the list with flickering/flashing/blackout issues. It would work

for a short period after a reboot, power down, or unplugging power. This started

happening to me 4 months after my Applecare ran out.

I was running this setup for almost a year with my late 2013 iMac (all firmware updates

applied) without a problem. Previously was using it with my MacMini Server from new.

I read this thread and some others about connecting via the Thunderbolt port. I had an

extra TB cable so decided to try it. Connected my iMac to the TB display's TB connector

and it worked and has been working for several weeks now.

So, has anyone that was able to solve the issue by this method taken the TB display

in for repair. Was it logic board or the Thunderbolt cable?

BTW, it seemed all else was functional as I could go into System Report and see all

the various ports active in the display.

I would like to share my experiences concerning these flickerings. It is reported elsewhere in the forums as well - I deciced to post here. I was plagued by the flicker as well. No chance to reproduce it. Even worse, the entire system becomes frozen after some time of flicker.

Now, I finally managed to reproduce and resolve the problem. I am running a MacPro late 2013 Yosemite 10.10. and Windows 8.1 in Bootcamp. Monitor is a Dell p2415q connected via TB. Screen flicker in Yosemite and Windows.

It appears to be the screen refresh rate of 60Hz which is causing sync problems - the screen flickers - and at a certain point freezes, while all sound happily continues to play in the background. Unfortunately there is no easy way to lower the refresh rate in the system settings, but: Using secondary MST on my Dell p2415q forces a refresh rate of 30 Hz. I dont know what to say: The problems are gone. No more flicker, no more hang. The downside: a 30Hz refresh rate is no real joy.

Actually running the Mac at 1080p/50Hz in Yosemite or native in Win 8.1 3840x2160/50Hz (CRU-utility from monitortests.com can create a custom resolution) Unfortunately I do not have a solution for Yosemite - no useful resolution at 50Hz. Switchres X does not let me create anything "Retina" at 50Hz > 1080p. I can run Yosemite at native resolution at 50Hz, but then everything becomes somewhat tiny...