I think I finally solved the problem with the following method: The external display on my Mac mini 2020 (M1 Mac) was flickering, so I switched the OS and switched the HDMI port to a different one, but no improvement. However, one day, I thought of something and switched to a thick HDMI cable that I use to connect other devices (4K TV), and it became stable like a lie. Did switching to a thicker cable help?
The thicker cable that worked so well didn't have any special cable specifications on it, it just said "High Definition Multimedia Cable".
I also tried another experiment. I also found a very thin and flexible type of HDMI cable, so I switched to that. This one was also stable and displayed well. What does this mean? In other words, I would have preferred a thicker, more solid cable, but the thin one displayed fine. I think a good quality cable will solve the problem. You should all try it.
Same problem here on a MacPro 2019 Big Sur 11.3.1 with 2 external monitors (so it does seem to be software related and not only happening on MacBook/MacBookPro). After waking from sleep or when waking the monitors, the resolution change in both my displays continuously. Each time, the colors and the resolution changes are different and it make take up to 1 minute until it stabilizes and become usable to enter the login password. I also get random flickering in the terminal (completely red display on some apps for 1 second or so). I tried multiple HDMI cables but nothing seems to work. Tried reseting NVRAM too.
I'm having the exact same issues. I also have the 27" 2017 iMac (iMac18,3) with 4.2 GHz Quad-Core Intel Core i7, though these problems seem to extend to other models as well. Like many others here, I'm also running multiple Adobe apps including Photoshop, After Effects, and Illustrator, and the issue definitely seems worse while working in those. I've also observed that it gets worse with mouse movements and/or keyboard input (for example, I frequently use Cmd+Tab to switch apps, and I often see intense flicker & drop-shadow-esque artifacts when switching in this way). It seems likely that Adobe is at least partially accountable, but I never saw anything like this before updating to Big Sur.
I also start suffer at thus issue very first time when i was updated on big sur when it was released.
macbook pro 2020 16” i9 and radeon graphics.
i have two screens whit dell new displays connected to lenovo tb3 dock
setup was working just fine before big sur bit not after that.
my primary screen is flickering on top of screen and not stop until I shutdown the display power and wait 5sec and then power it on again and after that it works just fine until i shutdown the mac…
so something related to graphics drivers on big sur…
hope Apple fix this on updates or next macos release.
I'm really surprised this hasn't been addressed? I'm having the same problem with the bottom inch flickering. The first time this was seen was 11 months ago, yet people have been commenting on this problem the whole time. Come on Apple, I didn't upgrade to Big Sur for this very reason, I wanted to wait out the bugs, and after 11 months, this one is still here.
I have the same problem: 2017 iMac 4.2 GHz Quad-Core Intel Core i7 running OSX 11.4 Big Sur.
It happens especially when using graphics or video programs. I tried everything. Please give me some advice. reset NVRAM reset SMC new fresh installation I still couldn't find a solution. I connected the second monitor, and the flickering continues on the second screen, too. (both have) I used the screen recording, and I saw, in the recording, everything seems fine; there is no flickering in the screen recording, but in real-time, there was a lot of flickering. So, the recording shows nothing. I guess it is not a screen hardware problem (the second monitor has also flickering when I connected) What do you think? Is it about the GPU, graphic card, or processor?
Hey I managed to fix this bug Just use Scaled display resolution. Not everyone likes it, but it will fix a bug))
How to resolve flickering issue in Mac air ... After update to the big sur the problem occurs ... Please help
Same problem on my MBP 15" Mid-2019 with the i9 for almost a year now. It started with flickering and ended up in a complete black screen (just a small notch on the top of the screen remains). Super mad at Apple for not fixing this for a whole year now.
I found a workaround by unchecking "Automated Graphic Switching" in the Battery settings. But the Battery is insanely draining.
I already resetted SMC, NVRAM/PRAM, Secure Boot, created a temp user, wiped all partitions, reinstalled Catalina, updated back to Big Sur, Apple System Diagnostics (shows no problem with the system), changed cursor size, deactivated True Tone / Night Shift, updated to Monterey beta, checked connector-type properties of the iGPU using IORegistryExplorer, used gfxCardStatus and much more...
Any answers yet? I just upgraded to the Big Sur and my screen is being taken over by the flickering lines. I can't work on the computer like that. MacBook Pro (13-inch, 2019, Four Thunderbolt 3 ports)
Hey I got the solution that work for me which is different from al others :-
step one :- press the power button , after pressing the power button , Hold "command + R" button .
step two :- you will see macOS utilities > Click on Restore from time machine backups .
step three :- after clicking time machine , I find out that I have no backups in my backup , So, what I did is just open time machine with two or three hours , without restating .
step four :- If you complete three or four hours , then just click to restart . And after that everything work fine .
I don't know what make it work , but to be very precise I have a flickering issue , and there are two times I faced same problem which I solved through the same solution , thankfully it work .
let me know if this work for you not . Thank me later
This is an extremely weird fix, but it works, which makes me think this is a software issue and not a hardware issue.
open up textedit: Applications > TextEdit
Copy and paste this html file [this is just a little javascript animation]
<!DOCTYPE html>
<meta charset="utf-8">
<body>
<script src="https://d3js.org/d3.v4.min.js"></script>
<script>
var svg = d3.select("body")
.append("svg")
.attr("width", 500)
.attr("height", 90);
function keepinItRed() {
var timeCircle = svg.append("circle")
.attr("fill", "red")
.attr("r", 20);
repeat();
function repeat() {
timeCircle
.attr('cx', 40) // position the circle at 40 on the x axis
.attr('cy', 60) // position the circle at 250 on the y axis
.transition() // apply a transition
.duration(1000) // apply it over 2000 milliseconds
.attr('cx', 450) // move the circle to 920 on the x axis
.transition() // apply a transition
.duration(1000) // apply it over 2000 milliseconds
.attr('cx', 40) // return the circle to 40 on the x axis
.on("end", repeat); // when the transition finishes start again
};
};
keepinItRed();
</script>
</body>
</html>
Save it to the Desktop.
Open it in any browser [chrome, Firefox, safari, etc].
Keep it open, but put it in a corner.
Voila.
I stumbled across this while working, my MacBook also started flickering after an update, but I noticed that the flickering stopped if the site had a javascript animation running in the background [also any animations in the native macOS, such as the loading cursor].
This is by no means a permanent fix, but in case you're out of options or need your laptop to work [like I do], this'll be a stop fix.
This bubble is now calming to me, kind of like a virtual Newton's cradle desk toy.
MAY THE RED CIRCLE SAVE YOU. credit to Mike Bostock for the underlying lib and code.
I meet the same flickering issue on a brand new Macbook Pro 16 inch 2019, 2.6Ghz 6 core Intel Core i7, running Big Sur 11.5.2. Once connected to my Dell U2518D external display, it flickers every 6 seconds, approximately.
I do not meet this problem with the old Macbook Pro 15 inch 2017, 2.8GHz Quad-core Intel Core i7 that I own, that runs Catalina 10.15.7.
As I work on an external display the whole day, for computer graphics, this is a severe trouble.
Same problem for me too with Big Sur OS using the Dell monitor model U2412M. I have two Dell monitors using Dell mini port dock, and only one monitor is having the flickering issue. After i disconnect the cable from the monitor to Dell mini docking port (cable being used to connect to the flickering monitor was the Basics 4K Mini DisplayPort to DisplayPort) and replaced by the direct connection via the USB-C type, problem fixed. So now the Dell mini dock is only being used for mouse, ethernet, etc, since both monitors are now connected to the Big sur mac book via direct connection using USB-C type-connection.
No fix but adding my two cents. For me issues occurs with thunderbolt docks (2 tested Cable matters, and Pluggable dock). MBP 16" i9 32 GB new less than 2 months old. For reference the same docks plugged into my Linux laptop work fine. Once flicking starts Unplugging HDMI cable or removing the dock connection causes a kernel panic and reboot
I was able to reduce the flicking by never closing the MBP, and installing an app to prevent sleeping. This reduced the issue, but it comes back typically during video conferencing.
I can't find the reference at the moment, but there is another thread that indicates this is a bug in Big Surs implementation of Thunderbolt which occurs with 4k or higher monitors connected via HDMI.
I was hopping the recent 11.6 upgrade would sneak in a fix, but no such luck yet. Hope this helps someone.
As others have noted changing the resolution to scaled, randomly adjusting supported refresh rates works sometimes (not consistent).