Try setting up a central ground strip if this has not already been done.
To this, Connect the incoming service ground, all shields and any other grounded systems, also if this is a tower or desktop PC, connect the 5v common PP pins to the ground plate.
For any system or power supply that is referenced to ground, use the respective power supply common connection for a return, do not use a ground conductor as a return path.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.