I currently have two Pan Cams in use. At least once a week I have to reprogram the waypoints on each camera.
Is it possible your base is moving? Mine does that sometimes. Try some double stick tape or something with the pan bottom and see if this still happens.
The camera is mounted on a 1/4-20 bolt and it is tight.
Well that changes the game in full now doesnt it. Maybe the internal gears are skipping thus creating a different point of contact for the beginning and end cycle?