Solved my sluggish keyboard?

[Wanton38]

I have a Dell XPS 13 9300 attached to a UD-ULTC4K which has an old ACER Screen thro’ VGA to Display Port, a Microsoft keyboard and NTrust wireless mouse (the dongle is) connected through an Anker USB hub that connects to one of the UD’s USB-C ports. I run Ubuntu 18.04 with DisplayLink drivers installed.
All worked without any problem at set up.
I was in the habit of powering on the Dell laptop then immediately using the Microsoft keyboard to login etc… However I noticed that I was having considerable problems because both the responses to keyboard key presses and movements of the mouse were very slow and sluggish. The system was unuseable. It was driving me up the wall.
I discovered by accident that if I used the keyboard or touchpad on the laptop then the rapid response they provided was also available through the UD-attached keyboard and mouse from then on. In particular if I login using the laptop then transfer to the attached devices the responses are as rapid as normal.
Can anyone explain why this might be?

[Joshua_H]

Hello,

Thank you for contacting Plugable support! Sorry to hear about this issue. I’d be more than happy to assist you.

We don’t officially support Linux with our DisplayLink based docking stations, so we’re not actively testing this kind of scenario. Normally I’d expect this kind of issue to be caused by driver performance problems with the DisplayLink USB graphics, but based on your description I don’t think that’s the case here. It’s quite odd that the issue doesn’t happen if using the laptop first, and then moving to the attached devices just fine.

Is the Microsoft keyboard wired or is it also wireless like your NTrust mouse?

What happens if you connect those devices directly to the dock, removing the Anker hub from the equation?

Please don’t hesitate to let us know of other questions.

Thanks again for contacting Plugable support and best wishes!

Joshua Henry

Senior Engineer | Product Owner
Plugable Technologies