Ultrabook keyboard malfunction after unplugging from Plugable 3900

Installed Plugable 3900 and all was well. I unplugged my ultrabook from the docking station and found that the keyboard on the ultrabook was throwing up random alpha-numerics unrelated to the keys pressed. Now I can’t remember whether the ultrabook had been properly switched off or had been left in ‘sleep’ mode. Could it be that by not properly releasing the USB 3 port on the ultrabook from the Plugable docking station it caused the keyboard not functioning properly? I run Kaspersky Internet Security on all my machines for many years and have never seen this phenomenon. and running a full scan on the ultrabook shows no suspicious activity. Having plugged in the ultrabook back into the docking station it seems to work properly again. Has anyone else come across this and if so what was the solution?