Thanks for getting in contact with us. I’d be more than happy to help you with your Plugable dUD-3900. In order to better assist you, I’ll need a bit of additional information.
First, can you completely reinstall the DisplayLink drivers by following these steps:
Disconnect the adapter from the computer.
Run the DisplayLink Cleaner tool to completely uninstall existing DisplayLink Software:
Download driver v7.6 M2 from the below link and follow the installation prompts.
Reboot the computer.
Replug the adapter to the computer. Allow several minutes for the driver to enumerate and for the firmware upgrade to complete.
Does this help at all?
If not, could you please provide the logs produced by our tool Plugdebug, you can find it here and then send them to me at email@example.com.
Once we have those logs, we’ll start trying to figure out what exactly is going on with your setup.