Flickering, lines, and ghosting on Dell monitor whenever f.lux activates on MBP M1 Max
I just upgraded from a 13" MBP with Intel to a 14" MBP with M1 Max. I setup my new system from scratch and manually installed all applications. (I didn't want to bring over any cruft via Migration Assistant)
Here are the specs of my setup:
- MacBook Pro M1 Max (14-inch, 2021)
- 10 core CPU, 24 core GPU
- macOS 12.3
- Dell 27" U2720Q
- 4K resolution scaled to double 2560x1440
- 60hz (no variable refresh rate)
- Connected via USB-C (have tested connecting it direct to mac, through a Dell TB3 dock, and through a Promise TB3 dock.)
- f.lux v42.1
The most bazaar things are occurring whenever f.lux starts or stops adjusting the color temperature. Dark gray areas will start flickering or pulsating but at such a high rate that it's near impossible to capture on camera but very noticeable in person. Next, vertical pinstripe lines will appear. And finally if you adjust the screen zoom, the flicker will continue, the lines will sometimes change, and then ghosting will appear. It looks like plasma/OLED burn in (visible in dark backgrounds) but all of these issues go away instantly upon rebooting the computer. At first I thought this was all random or that my monitor was starting to fail until I realized a pattern where the issues start whenever f.lux hits one of the transition points where it starts adjusting the color temperature. About mid-way though the process, the issues sometimes go away on it's own but them come back once gets closed to the end of the ramp as shown below. Also the issues never seem to occur during the day.
I've heard of other people having issues with their displays but haven't seen anyone with my exact symptoms so it's unclear of this is actually a f.lux issue, or something deeper down into the macOS level.
For example this article mentions users having issues after upgrading to macOS 12.3 but mainly displays not working at all/no signal. I haven't had that issue. I also found this thread where a user included this video which demonstrates the type of flickering I'm seeing. I've tried my best to capture this myself and this video shows the lines and ghosting and this video shows the flickering.
Again I have no idea if f.lux or macOS is at fault here. I'm just trying to bring awareness as it makes my new Mac infuriating to use and I welcome any comments from other users which may have the same or similar issues.
herf last edited by
@afwp89789tyzfsw78 hmm we did notice that one of the new miniLED settings (HDR? ProMotion?) creates some artifacts. I think they're intended to be below the visual threshold but can be more noticeable at times.
Can you try adjusting your display settings to see if there is a combination that makes this better?
@herf The issue does not occur on my internal display (which does have miniLED and ProMotion). The issue happens only on my external Dell display which does not have either of those features. I have tried changing the refresh rate (60hz/30hz) and the issue happens with both. I've also tried creating a new color profile but the issue occurs with custom profiles as well as the default.
So I think I narrowed down the issue to something related to macOS 12.3 as I'm seeing many reports like this one and one thing in common is USB-C displays. I switched from USB-C to HDMI and for the past two days I have not had the issues.
I've upgraded to macOS 12.3.1 which is supposed to fix external display issues and while my issues aren't 100% resolved, this particular issue I was having with the flickering which occurred when f.lux was adjusting the color temperature has gone away, so I think this is resolved and was a macOS issue which was conflicting with f.lux.