Monterey 12.3.1 External Monitor/Display Issue - No Longer Outputting Signal

Update: My monitor is still not working right. I am using a 4k Samsung LU28R55 monitor hooked up through USB-C to display port Moshi cable. After upgrading to 12.3.1 I thought the disconnection was solved but it hasn't been. The monitor doesn't come back on if the computer has been sleeping for more than 20-30 minutes. I have spent a total of at least 5 hours working with two apple support reps. The first rep said he would be taking the lead on my case and I spent 2.5 hours working with him. We tried to grab computer logs but that failed. I sent in information and setup a follow-up appointment with him only to be ghosted. I followed-up and then spent 2.5 hours working with the second rep trying to capture logs and upload the information. I had to repeat all of the information the first rep asked me. Capturing the logs failed again.

My monitor is still not being recognized well by my mac mini 2018 intel and the HDR content randomly can be selected by unplugging and replugging. My HDMI port has similar issues and when I can get that to work the colors bleed slightly. I have also notice an issue where I will have an apple headset plugged into the back of the computer and it will stop recognizing it. Between three genius bar visits, text messages, and two support calls with Apple I have spent over 14 hours trying to get this computer working which is ridiculous. If my genius bar visit this weekend or 12.3.2 doesn't fix this I am going to demand a replacement from Apple.

I'm having the same problem... MBP 16 w/ AMD Radeon Pro 5500M 8 GB and my display is a Dell u4919dw.

9 times out of 10 when I plug the display into my MBP nothing happens (the monitor stays black and/or displays no signal from device). The other 1 out of 10 times it will sense my MBP but the resolution can only reach 3840 x 1080 rather than the full 5120 x 1440. Have wasted hours trying to debug and have tried everything including deleting the .plist files but nothing has worked! Really hoping 12.3.2 fixes it...

I tried it - thanks - didn't work. I have the same issue, MacPro 2018 - 15.6" FHD 1080P + Touch - N1F PRO. This has got to be fixed soonere than later, a huge ripple in the. remote work industry....com on Apple, can we get a fix before the week is out?

kristel147, I can only hope your plea is answered. I have been down for a month now for my second monitor and it is having a profound impact on my ability to work. After the .3 update my monitor now only kinda works. It does sometimes display properly then all throughout the day it dims to where I can barely see what it on it, then gets bright, then blacks out completely and continues to behave like that all day long. The wait for a fix on such a simple peripheral is tiring.

I am beyond frustrated that this problem has been going on for over a month. We have a brand new MacBook Air with Monterey iOS 12.3.1 already installed. When we have tried to make it work with literally every monitor in the office (all LG 27UD88-W), the same black out problem occurs. We have had IT on it all week. It is completely random as to when the monitor will work and when it won't. FIX THIS NOW, APPLE. HOW HAVE YOU NOT FIXED THIS YET? It is clearly happening with all monitors, not just LGs. This is profoundly impacting our ability to work. I have been a loyal Apple customer for over 15 years but for the first time, I am actually considering moving us to PCs. I resent Apple's proprietary issues, as this is certainly not the first time, nor will it be the last, that a non-Apple product won't work with an Apple product. I AM SO MAD.

It's not just DP though. I've got an old DVI monitor and even that one just says "No Signal" and only rarely actually displays the image after some type of refresh, like waking my Mac Mini from sleep mode or changing the resolution.

I've been in contact with Apple for a while and they even promised to send me an HDMI->USB-C adapter, so I can switch cables around and test the monitor with the HDMI port but I haven't received anything yet. I also talked to multiple reps but nothing's happening (okay, Easter holidays and everything but even before that), they just keep taking the same logs and "my" main rep hasn't contacted me in probably 2 weeks, even though they promised they would.

I did the same: bought a refurbished monitor Delll E228WFP because I thought the same model, working fine since installation of Mac mini m1 2020 but no: same problem. Even with update twelve. four now still the same. FRRRUUUSSSST.

Fixed: After trying all the advertised solutions for months I finally found a fix that has worked flawlessly for three days now.

I have a MacBook Pro (Monterey) and WAS using a "HyperDrive SOLO Hub for USB-C Devices" docking station to connect my hp external monitor via HDMI. The monitor would work for a few minutes, then start flickering and go off and on. The docking station was the issue (not a great design).

The fix was changing the Hyperdrive to the "Upgrow USB C to HDMI Adapter 4K@60Hz Cable Type C to HDMI Adapter [Thunderbolt 3 Compatible]" purchased on Amazon for . ZERO issues for three days.

I hope this helps someone with similar issues.

When running Windows on bootcamp (MBP16) there are no external monitor issues ! A software fix for mac os should be doable.

This is getting ridiculous. Problem persisted on Monterrey from the beginning.

"Just works".. Messing around for hours when this happens. Loosing focus AND productivity

Ok same issue - really frustrating.

Father's Mac Mini (M1, 2020) Have had two Apple 30" CInema HD Displays (c2005) running quite happily under Big Sur since he purchased it in 2020. Finally got him to move to Monterey and all went fine until the final reboot - both screens remained black. Over and over again, one monitor, different ports, different adapters did not matter - black. Took to nearby authorized mac repair shop, next day they charged us nothing (thank you!!! West Palm Beach MAC!!!), because they said - " Um, it is fine, the upgrade worked perfectly - and we ran it on 3 different monitors all ports no issues." Working for several days now with Apple tech ....no traction - is it the adapters or what? Displays btw are FINE - hooked each up to MacBook Pro - perfect. ????????

I was using 2 external monitors just fine until MacOS 12.3 (with universal control) came out. After a lot of work (including reinstalling Monterey), they told me that my M1 iMac can't handle 2 external displays. They sold me two HDMI adaptors, but only one display would work at a time. I returned 1 and wish I had returned both $70 displays as my solution didn't use it.

My solution was to buy https://eshop.macsales.com/item/OWC/CADPDL2HDMI/

OWC USB-C DUAL HDMI 4K DISPLAY ADAPTER WITH DISPLAYLINK and install DisplayLink.

Same issue, I have two Dell S2421HS monitors for my Personal MacBook Pro (using the HDMI Ports, the DP ports are used for work PC). I have an extra Apple TV A1842 (32GB) plugged my second monitor into the Apple TV > Add Display > Display Settings > Extended Display. Whenever I need the second display it works seamlessly until there is a resolution.

This has happened to me as well, Mac mini 2018 updated last week to Monterey 12.3.1. 2 HP Pavilion 27q displays. One connected via HDMI and the other connected thunderbolt. Both monitors worked for over a week and they worked fine this morning. But this afternoon when logging onto the computer only one monitor worked. I have unplugged both monitors for 3 minutes with the same situation. Both monitors worked great for a couple years and now after an upgrade one quits working.

Apple we need a fix.

My exact setup (HDMI + USB-C), except that I'm using the Mac Mini 2020.

The problem was (supposedly) fixed in 12.3.1 for the Mac Mini 2018, at least that's what the change log says, so it's weird that it still appeared for you too.

My new mini mac 2/22' setup w LG 49" HDR w C cable worked great, forgot to turn auto update off, next date, did not work, only under a hdmi cable, so not able to have my 5180x1440, did the update, worked great for one day3, then had to mess with, come back to the c once, now no longer works on C...