HDMI Displays 3 & 4 Stopped Working (Worked fine for 8 months) UD-3900C4

[demarcoretail]

3 external monitors worked fine for past 8 months, using plugs 1, 3 and 4. Now, plugs 3 and 4 are not working, able to use plugs 1 and 2.

[demarcoretail]

Tried hard reboot of UD-3900C4 device as well as connected laptop.

[adi]

Hi there,

Thank you for reaching out, and welcome to the community. It would be my pleasure to help!

The issues you are experiencing appear to be only related to the Alt-Mode MST connections. We will first want to ensure that you use the USB-C cable that came with the docking station. If you are using a different or longer cable, it might not support the necessary standards to drive HDMI 3 and HDMI 4.

However, if you are using the provided cable and are having issues, please email our direct support email address ( support@plugable.com) with “For ticket # 445667” in the subject line? In the email, please include the following information:

• Please provide the Amazon Order ID number for your Plugable product purchase.
  For your reference, an Amazon Order ID number has seventeen digits (separated by two dashes), and typically that information can be found here → https://amazon.com/orders
• Can you please keep the UD-3900C4 connected to your computer (even if it is not working as expected) and send us the output of our diagnostic utility PlugDebug? → https://plugable.com/pages/plugdebug 1

This will allow me to examine log files from your computer and help determine the next steps.

Please do not post the above information here in our public forum (it contains personally identifiable information)

If you have any questions, please don’t hesitate to let me know.

Thank you,

Adi
Plugable Technologies