So I've been noticing the last few days flying ( DJI GO) that my bird  has taken off at zero alt and returns to same point at -12.  Very  concerning.  Chatted with DJI and they instructed me to downgrade the  firmware and then reload the newest.  I did that.  Went outside to test  by running a Litchi waypoint mission.  Noticed that my waypoints were  designed at 150' but were running closer to 100'.  I paused the mission  before crashing into building roofs.  Had to put in Mode A to get  control and fly her back down.  This really concerns me as I fly near  airports and run mapping missions with dronedeploy.  Without a somewhat  accurate altitude I'm screwed not to mention it makes autonomous flight  impossible.

On a side note, how do you can you change adjust altitude mid Litchi mission?
Is switching mode to A the only way to get control of the bird mid mission?
Can you cancel a Litchi mission mid flight?

Its not Litchi that caused the problem.  It was either the bird or controller.  I've isolated it down to that.
Troubleshooting done:
bird firmware downgrade and re upgrade
confirmed controller firmware
uninstalled DJI Go and reload
Flew using ipad and also iphone
Flew using DJI go and also 3rd party app (Litchi)
Recal'd compass and IMU

Just got off the phone with DJI and they directed me to try and return  and replace at nearest Best Buy since its less than 30 days old and if  that doesnt work to send it back to them and be without a bird for up to  2 weeks....ouch

That's really not a DJI problem you need to contact litchi and you do know if something happens using that app it void your warranty

Suggest you try another IMU calibration along with a different level.

My level was off maybe 1 degree from others.  When I flew it a mile, the final altitude was showing -50 feet where take-off was zero.  When I found out my level surface wasn't so level against a longer level (about 1/4 bubble difference), it seemed to help quite a bit and my landing was much closer to take-off over a mile flight.  The nose on mine had to go up the 1/4 bubble for a IMU and seems well for now.

There was also some talk about the barometer maybe drifting a bit due to winds or a front, but I have the barometer int he iPad Air 2 cellular and that wasn't working until got got to iOS 10.1.  Prior 10 versions broke it.

Thats what happens when you launch from a tree top then fly down to ground level?  

gmccurdy@att.ne Posted at 2016-10-28 20:28
Suggest you try another IMU calibration along with a different level.

My level was off maybe 1 degr ...

how did you fix the 1/4 bubble issue? Re-calibrate EMI on a perfectly level surface?

billwish76 Posted at 2016-10-28 18:16
That's really not a DJI problem you need to contact litchi and you do know if something happens usin ...

How is this not a DJI issue?  This is a DJI problem that I checked in a 3rd party app to make sure it wasn't a DJI Go problem.