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

Upgraded my MB Air M1 to Ventura yesterday. DisplayPort had severe flicker and ghost picture on the LG, TB display was dead.

Networking (EthernetApple Filesharing) also had issues.

Reboot and so on, did not help. Switching to DP 1.2 did not work, black screen.

This morning, plugged all back in, all was back again and TB display works again. So same issue as with previous OS, its not really stable.

Has anyone received any helpful advice from support regarding this problem so far?

The last advisor (second level, not the "regular" phone support people) I talked to had me try a lot of things, including a factory reset, but none of it helped. He also filled out some form with me and sent it to the "engineers", later he called to tell me that he'd received a reply from them but I haven't heard from him since then (more than a month ago by now) and I also can't seem to get in contact with him anymore because the supportmessaging link I got just shows some error and the e-mails I send to "acsupportcase" directly go unanswered too.

Same issue Mac mini 2018 + USB-C + Acer ACER Nitro XV340CK

I only could make it work using HDMI

Stopped working as well on my MacMini 2018 with an Asus PA27 AC on thunderbolt, but switching to HDMI works as good workaround.

Vention 5-in-1 USB-C Hub with HDMI port

Same for me!! I've returned 1 monitor thinking it was incompatible, and now have another monitor (Innocn) that is showing the same signs - not working because of this recent update. APPLE PLEASE FIX

In my case: using the second plug in on my 2007 Dell E228WFP monitor with an 9 USD Adapter for the Mac Mini 1 solved the problem.

Error reproduced on 12.4.

Macbook Pro 13" 2016.

Using HDMI, Apple's own usb-c hub, on a display/setup that used to work before 12.3.

In my case: using the second plug in on my 2007 Dell E228WFP monitor with an 9 USD Adapter for the Mac Mini 1 solved the problem. It works without any problem since then.

I had this exact same issue with my Mac mini with HDMI. Solution was using display port instead of HDMI port. My guess is you have faulty USB-C port most likely.

Same problem after upgrading to 12.3. Was using a portable external display driven through the thunderbolt usb-c cable. Not keep on saying no signal!!! I really regret upgrading and this is how you break customer's confidence in your product.

Same issue. being forced to upgrade to Monterey 12.3 due to company policy and suddenly second usb-c screen doesn't work.

Config: MAC Mini 2018 + 2 x USB-C connected LG 34WK95U Monitor

Tried the following although doesn't work at all.

• both monitor's display port already downgraded to 1.2 rather than 1.4
• separate the usb-c monitor connection - now connected to the far left and far right rather than side by side

Do not want to fall back to 1 x usb-c + 1 x hdmi/display port as the colour tone is not sync

Please fix it ASAP.

Same issue here! I've got a Mac Mini 2020 with the same setup I used on my old Mac Mini: Main monitor connected via HDMI, second monitor connected via DVI->USB-C adapter. It worked there but doesn't work on this one. I already updated from 12.0.1 to 12.3 and now it displays the correct monitor information for the second monitor (previously it said that the second monitor is a 46" one?!) but when I switch it on, I still only get the "No Signal" message and then the monitor switches to sleep mode (I can still move the mouse cursor to it).

Monitor: 49" CRG9 Dual QHD Curved QLED Gaming Monitor

Equally experiencing this frustrating issue after updating to 12.3 on MacBook Pro (16-inch, 2019). HDMI works via the dock station, but the resolution and color is so bad that my eyes hurts! Apple needs to resolve this ASAP.

Forgot to mention my monitor: It's a Acer V193 (19" 5:4 with 1280x1024), connected via a DVI->USB-C adapter by KabelDirekt that was working fine on the old Mac Mini (can't remember the macOS version but pretty sure it wasn't 12).

Has anyone else got the problem with a DVI monitor/cable?