According to one user on the MacRumors Forums, the issue stems from macOS not recognizing a DisplayPort protocol version, which meant they had to change the version to an earlier one with poorer quality output. Some users have been able to crowdsource potential workarounds in the meantime. While many also report issues with USB-C displays, others also say that HDMI connections to the Mac are not being recognized. Other users have shared similar experiences. I have had to resort to connecting it to my old TV with HDMI connection. The odd occasion it will display a picture but once I shutdown or restart the mac mini it does not display a picture. As one user on Apple Support reports:Īfter updating my Mac mini today to 12.3, my monitor now no longer displays an image via USB-C, just keeps saying on no signal on the monitor. Adding to the list of issues, users are now reporting that the update is causing problems with external monitors.Īccording to users on the Apple Support and MacRumors forums, some external displays connected over USB-C are no longer detected by Macs after updating to the latest macOS update. In the ten days since the update became available to the public, users have already reported issues with the update bricking Macs that have had logic board replacements and problems with using game controllers.

Following the latest macOS Monterey 12.3 update, users are reporting several problems when using external monitors, ranging from Macs not detecting displays at all to inaccurate screen output, according to posts on the Apple Support and MacRumors forums.

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