Touch Screen recognized in Settings | Mouse and Touchpad but touches do nothing

I'm trying out a new touchscreen with LinuxCNC 2.91 on RaspberryPi today. 

The Touch Screen is recognized in Settings | Mouse and Touchpad; two instances of wch.cn TouchScreen, however touching the screen has no effect either on the desktop or from within Axis.

Do I need to enable a driver, or do something special to get this to work?
The keyboard, mouse etc are also recognized and they both seem to work just fine.
 

Might have better luck with this in the Debian forums, it is Linux related.