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mattintheweb Author

Level 1

4 points

HDMI external monitor not working anymore

I have an external monitor at the office, that I plug on the HDMI port of my Macbook Pro (early 2015). It used to work fine before I was confined home back in March. Now that I'm back at the office, it's not working anymore: when I plug in the screen, it's just not detected.

However, displaypolicyd spikes my CPU and my macbook pro becomes really slow for a while. It actually worked once, but I'm not sure why. I tried under a guest user account, but it's the same, which have me thinking it's not due to a third party software.

Can it has something to do with an iOS update I installed since March? I use Catalina 10.15.5.

MacBook Pro 13″, macOS 10.15

Posted on Jul 15, 2020 6:29 AM

Top-ranking reply

mattintheweb Author

Level 1

4 points

Posted on Jul 17, 2020 1:51 AM

I updated to Catalina 10.15.6 and made a few new tests:

it works fine with other screens
the same issue happens when I plug this screen in a Firewire port or on another computer

I guess it's the screen then… :(

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HDMI external monitor not working anymore

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