Armed/disarmed loop when connecting to pixhawk running ardurover

I have a pixhawk4 running ardurover firmware on a ground vehicle. I can connect and set up the parameters in Mission Planner but when I try and connect to QGroundControl (3.5.6 and 4.0.1) it loops continually in to a state of “Armed” and “Disarmed”
For ease of mission planning I would prefer to use QGroundControl.
Anyone have any idea why this might be happening?