Shortly after takeoff I always get compass errors and the inspire switches to ATTI mode for anywhere from 10 to 30 seconds.. sometimes it goes back and forth a few times.. after that it seems to stop.

I have checked everything I can think of. I am in a huge field with no power lines, cell towers, or stuctures of any kind. Cell phone is left in the car, car keys are left in my backpack.. I always fully calibrate compass first before flying.

Is this a bug in the software or do I need to take some further step to prevent this?

I am learning to fly in ATTI mode to gain experience, but when this happens unexpectedly its nerve wracking sometimes especially when its windy or i am already moving and have to regain control quickly.

Any ideas or others who have this problem?

There is another thread already opened about this - i missed it. Sorry for the duplicate posting.