Hi,
I recently started having horizontal lines on my external monitor. Before everything was running fine. On my MacBook Air M1, the display is normal. The lines are independent of the resolution. At first I could solve the problem by turning the monitor on and off. But now it doesn't work anymore.
Has anyone had a similar problem before? What could be the reason?
MacBook Air 13″, macOS 12.4
Thanks for reaching out, PaulMuaddib.
It sounds like you're noticing some lines on your display. We can help.
Since you've already tried adjusting the resolution without any change, it sounds like this could be a hardware issue. But, just to rule a few things out, let's go ahead and start your MacBook Air in safe mode and see if there is any change: Start up your Mac in safe mode.
In particular, check out these steps:
Start up your Mac with Apple silicon in safe mode:
On your Mac, choose Apple menu> Shut Down.
Wait for your Mac to shut down completely. A Mac is completely shut down when the screen is black and any lights (including in the Touch Bar) are off.
ress and hold the power button on your Mac until “Loading startup options” appears.
Select a volume.
Press and hold the Shift key, then click Continue in Safe Mode.
The computer restarts automatically. When the login window appears, you should see “Safe Boot” in the menu bar.
When starting up in safe mode, keep in mind that "Safe mode prevents your Mac from loading certain software as it starts up, including login items, system extensions not required by macOS, and fonts not installed by macOS. It also does a basic check of your startup disk, similar to using First Aid in Disk Utility. And it deletes some system caches, including font caches and the kernel cache, which are automatically created again as needed."
If things look unusual, this is expected behavior. Restart normally and see if the issue persists. Learn more here: How to use safe mode on your Mac.
Take care.
Thanks for reaching out, PaulMuaddib.
It sounds like you're noticing some lines on your display. We can help.
Since you've already tried adjusting the resolution without any change, it sounds like this could be a hardware issue. But, just to rule a few things out, let's go ahead and start your MacBook Air in safe mode and see if there is any change: Start up your Mac in safe mode.
In particular, check out these steps:
Start up your Mac with Apple silicon in safe mode:
On your Mac, choose Apple menu
Wait for your Mac to shut down completely. A Mac is completely shut down when the screen is black and any lights (including in the Touch Bar) are off.
ress and hold the power button on your Mac until “Loading startup options” appears.
Select a volume.
Press and hold the Shift key, then click Continue in Safe Mode.
The computer restarts automatically. When the login window appears, you should see “Safe Boot” in the menu bar.
When starting up in safe mode, keep in mind that "Safe mode prevents your Mac from loading certain software as it starts up, including login items, system extensions not required by macOS, and fonts not installed by macOS. It also does a basic check of your startup disk, similar to using First Aid in Disk Utility. And it deletes some system caches, including font caches and the kernel cache, which are automatically created again as needed."
If things look unusual, this is expected behavior. Restart normally and see if the issue persists. Learn more here: How to use safe mode on your Mac.
Take care.
Macbook Air M1 - uniform horizontal lines on external display (Dell U2720Q)
