I finally got up the courage to try a mission with 2.05. I set up a very simple mission - takoff to 10 meters, loiter time 60, land. All the coords were very close to each other so it should land about where it took off. The first two times I started the mission, it went up a few feet and then bounced around the ground like it was at altitude and loitering. The third time was very different - Up it went very high - seemed like more like 100' rather than 10 meters - and I was sweating bullets. It then loitered for what seemed like much more than 60 seconds, but I bit my lip and waited. It then began a landing pretty much on target, but at about 20 or 30 feet it decided to head towards a corner of the park and I aborted, though it might have landed OK if I had more room.My theory is that there may be probs in the altitude sonar/ baro switch. When I lock height, it bounces a lot if within sonar range, and sometimes just shoots up without stopping. I verified the sensors by loading Ardupirate code - unit is very accurate on sonar height with this code, so I know the hardware is OK.The landing way off target was puzzling. I let the GPS run for a while, but maybe coords changed. I wish I would have had more room to see where it ended at.I also assumed that mission end at 'land' stops the mission, but soon realized I had to kill mode switch as soon as it landed or it will repeat the mission. Might be nice to wait for a throttle toggle to start again.Anyone else seeing this?