Thanks for posting! I’m sorry the dock stopped working properly with your Surface after the DisplayLink driver update. I’d be happy to help!
Since the problem occurred after the driver update, the first step to clean the DisplayLink driver completely from your system and re-install the latest version we recommend. Please follow these steps:
Disconnect the dock from your Surface and please remove the power cable from the dock so it turns off completely. Please keep it disconnected until the last step.
Uninstall the DisplayLink Core software from the Control Panel -> Programs and Features. Don’t worry if this fails, just move onto the next step
Download, extract and run the DisplayLink cleaner tool, found here:
Once the Cleaner has been run, reboot (even if not prompted to)
Now download and run the 7.7 M4 DisplayLink software, found here:
Reboot, even if not prompted to
Once you’re back in Windows, reattach the power cable to the dock first. Once the dock is powered on, reconnect it to your Surface which will trigger the final portion of the installation
Hopefully that gets the DVI output working properly. Let us know the results when you have a moment and we can determine the next steps from there.