On video stream, monitor disconnects

Hi, I have been using the TBT3-UDC1 hub with two monitors connected. When I stream from Netflix, Prime video, Spotify web player, etc. one of my monitors seems to lose signal. From what I’ve read this may be a HDCP issue. The monitor that stays connected is using DP → DP, whereas the monitor that disconnects uses an DP → HDMI active adapter (link below). Can you identify any changes in setup that may correct this issue? Thanks for the help!


Hi Preston,

Thanks for posting!

That DP to HDMI adapter you linked appears to support HDCP 2.2, so I would expect this to be fine. Let’s see if we can better isolate the problem by trying the items below:

  1. If you swap the DP to HDMI adapter to the other DP output on the dock, do you still see the same issue?
  2. Can you swap out the HDMI cable for a different one to see if it behaves the same?

Thank you for giving us a chance to help!


Hi Mitchell,

Thanks for the recommendation. Upon swapping the display port cables on the hub, I observed the same behaviour on my other monitor that does not have an DP -> HDMI adapter. This leads me to believe that it is a problem with the hub rather than the adapter. Is there any sort of firmware update that could correct this issue, or will a replacement unit be necessary? Also, this behaviour is occuring on DP Secondary of the hub. Thanks for the help.


Thanks for getting back to me with these results. Agreed that based off your testing, the DP to HDMI adapter or the monitor are likely not the culprit.

At this point, I’d like to request some logs from your system in order to best investigate further. Could you please keep the Plugable dock connected to your system (with everything still attached), then navigate to our PlugDebug tool and follow the instructions there?

This will create a ZIP file on your Desktop containing system logs and information. Please send these log files to us at support@plugable.com with subject “Ticket #305759”.

Thank you!


Thanks Mitchell, I have just emailed the debug logs.


Preston reached out to us with their log files but we were not able to find a clear explanation of why this flickering was occurring, seemingly related to HDCP content.

However, a different laptop with a Thunderbolt 3 port did not see the same problem, so we highly suspect some host issue with the Lenovo computer.


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