Unexpected activity pause during course navigation in trail running activity?

Auto pause is not on, and I'm sure I didn't actually hit the start/stop button.  But a couple of times now I've been running with map screen up navigating a saved course, and I look down and the activity is in the pause screen and has been paused for a little while as if I've pressed the start/stop button- which can be very frustrating as then the gpx track later is wrong, Strava segments are missed, etc.  My main question is whether this is a bug or if there is some condition that can cause the activity to pause on its own or through unexpected screen touch(s)?  Again, auto-pause is not enabled and I've only seen it happen a couple times.