Only one monitor awakes when bringing MacBook Pro out of sleep mode

I am using the two LG 27UD58 monitors with two Displayport cables. When I wake my MacBook Pro (2019) out of sleep mode, often only one monitor is recognized and comes back on. I will have to unplug the USB-C cable from the MacBook, and then plug it back in, to get the second monitor to be recognized and turn back on. Any help you can offer so that I might better understand what is occurring is appreciated.

Thank you.


Thank you for contacting Plugable support! Sorry to hear about this issue. I’d be more than happy to assist you.

Since these displays are connected directly via DisplayPort, I wouldn’t expect you to encounter this sort of behavior. Normally, this kind of behavior is only seen on occasion when using a DP to HDMI conversion for the displays.

We have a troubleshooting tool that helps us find out what is going on in situations like this. Please plug the dock with your displays attached into your computer, then go to this page and follow the instructions there:

If possible, I’d like to gather diagnostics from the system while it is in a broken state.

Also, can you confirm you’re using the Thunderbolt 3 cable the dock shipped with? Or if you’re using a third party cable?

Please don’t hesitate to let us know of other questions.

Thanks again for contacting Plugable support and best wishes!

Joshua Henry

Senior Engineer
Plugable Technologies |

I have run the diagnostic program and emailed the file to

I do not believe that the cable I am using for this monitor is the one that shipped with the dock. I have that cable hooked up to my second monitor.

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