Help: 40 second blank videos on stickup cam 3rd gen

I've got a number of ring cameras on subsciption and have recently added a 3rd gen stickup cam set to Outdoor mode and running on battery. Camera works quite well capturing movements and on valid recordings the length of the video stops when no further motion is detected so the recorded length varies. But from time to time it will record blank videos that are exactly 40 seconds long. I am not sure what is triggering these recordings and why they are always 40 seconds long. Anyone got any idea on what's going on?Settings are as follows:Customisable motion zones: enabledSensitivity: MaxPeople only mode: DisabledVideo recording length: 60 seconds