No position change of Motion Controller

Hi,
I am developing a VR pawn with UE4.26 and VRPN input from ART DTrack.
Camera tracking of position and orientation as well as flystick button events are all fine.
I created a simple pawn blueprint with a scene node, a motion controller and a simple static mesh as a child of the motion controller.
Currently the static mesh solely follows the rotation input from the flystick but ignores any change of the location.
Has anyone encountered the same problem?