Had this issue as well doing autonomous waypoint routes in litchi. Mine (P4P v1) sometimes wouldn't even turn to keep the POI centered and the heading wasn't matching up from app to actual... Something was definitely messed up with compass or GPS. Mine also would drift to the left when flying straight from time to time. Sometimes worse than others. It finally crashed last week before I could try any other suggestions and now I'm left with parts lol Hopefully my MP2 doesn't have this issue. Following this out of curiosity should you ever solve it.