Thanks for contacting Plugable support! We’re very sorry to hear your U3 Communicator HD docks aren’t working properly.
Our basic troubleshooting process for this device is available at:http://plugable.com/2012/08/20/troubl…
As a first troubleshooting step, we’d like to have you try the dock with the included USB2 cable instead of the USB3 cable. This will help us isolate a couple of potential issues with USB3.
If you don’t have any luck maintaining a consistent connection on USB2, we’ll want to get some further details from your system, as we’ve had success with some customers by updating USB3 Host Controller driver and/or firmware.
If you’d like to work ahead in getting that information, the DisplayLink support tool will gather it from your system and output a .zip file you can email back to me. Instructions for use and download of the support tool are available at: http://plugable.com/support/tools/dis…
It’s also always a good idea to try eliminating any hubs or other devices between the docks and the PC during troubleshooting.
Please let me know how it goes connecting with a USB2 instead of a USB3 cable and we should be able to recommend some further steps.
Again, thanks for contacting Plugable support and best wishes-
MCITP Enterprise Support Tech