Only 2/3 displays working on 2023 M2 Pro Macbook Pro

I’m using all three DisplayPorts on the back of the dock to connect to three Dell S2716DGb monitors. Running macOS 13.5. DisplayLink Manager is installed and running. I can only get two monitors working at a time. The first (far left) DisplayPort won’t work no matter which monitor is plugged into it. Tried all USB C ports on the laptop. Any help would be greatly appreciated!


Thank you for contacting us, I am sorry this is not working as expected and I am happy to help!

This docking station relies on two graphics technologies to support up to three external displays.

The “Display 2” and “Display 3” outputs are controlled by DisplayLink USB Graphics Technology, this is a combination of software on the computer and hardware on the docking station which extends the capability of the computer to support more displays than the computer was designed to support. This requires installing the DisplayLink drivers for Windows ( ) or the DisplayLink Manager App for macOS and configuring macOS to support the external displays ( for macOS 13:, for macOS 11, and 12: ).

The “Display 1” the left most output when facing the back of the docking station, relies on the computer’s internal graphics controller, it utilizes USB Type-C DisplayPort Alternate Mode (“Alt-Mode” for short). This is an optional USB Type-C port feature which is not enabled on all computers. This relies on the computer’s built-in graphics drivers and requires the docking station to be connected directly to a USB Type-C port with Alt-Mode capability using the original USB Type-C data cable provided with the docking station. USB Type-C cables from other products, or purchased separately online may be charging cables that do not support Alt-Mode video data.

I recommend we start by verifying the docking station is connected directly to the computer using the original USB Type-C data cable provided with the docking station, this cable is about 3ft long, black, with black plastic molded ends. Each molded end has two small holes about 3/4 of the way from the USB Type-C connection to the strain relief, pictured below to help identify the cable:

USB Type-C “Charging” cables ( like the white cable provided with MacBooks ), adapter cables, or any devices between the docking station and computer will block the USB Type-C DisplayPort Alternate Mode video data and prevent the “Display 1” connected display from being detected by the computer.

Please let me know if this helps, or if the docking station is already connected to the computer using the original USB Type-C data cable provided with the docking station, or if switching to this cable does not enable the third display and we can proceed from here.

Thank you,

Plugable Technology

Thanks for the reply. I did already have the docking station connected with the included USB C cable. What other troubleshooting steps can I take?


Thank you for replying back, I recommend we get some additional details from the computer to see exactly how the system is detecting the docking station and external displays.

Our next step is to get some additional information from your system using our log-gathering tool: PlugDebug, when you have a moment:

  1. Keep the docking station connected to the computer with the displays and devices connected to the docking station
  2. Download and run our PlugDebug utility ( )
    2a) For Windows: Download the PlugDebug Utility, then Right-click on the PlugDebug application and run as administrator
    2b) For macOS: Click on the red button “Generate PlugDebug Report (Deprecated Pending Update)” to expand the section, select the PlugDebug utility from the Downloads pop-up on the Dock, or double-click if saved to the Desktop
    2c) Follow the on screen instructions to launch the application
  3. Click the “Start” button to begin gathering logs from the system
  4. When completed the application will pop-up a message with the name of the zip file containing the logs on the user desktop directory
  5. Please attach this zip file to your reply email to ‘’ with the subject line ‘Ticket #418788 - Attention Pat’

This will allow us to examine some log files from your system to help determine the next steps.

Thank you,

Plugable Technology

Just sent that email over, thanks!

Also not sure if it will be evident in the logs, but the dock doesn’t appear to power my computer. I had to have the MagSafe charger connected separately to charge.


To follow up, in direct email a full reset of the computer and docking station has restored normal behavior.

We’re closing this thread, but if you have any further questions please feel free to contact and we’ll be happy to help.


Plugable Technologies