Strangeness when running Cura

While running Ultimaker Cura (4.2.+) it messes with the keyboard. The program has the ability to talk to a few 3d printers (via a USB COM link of some sort (the install gives an option to install an Arduino library, which doesn’t make a difference either way). So trying to type while running Cura the keystrokes stall and then most of the time act like the key has been pressed for a second (aka typing 56.7 gives you 555555566666666666…7777777777 eventually).

It at first glance feels like Ultimaker is trying to talk to the keyboard in the same way as Chrysalis or the Arduino Ide is.

Still looking into what exactly is causing it but interested in if anyone else has had similar issues with this or any other software? model 01 running latest firmware from the git repository.
-Ultimaker Cura 4.2 - 4.8 tested