Hi! Have just started flying my brand new PV2+ & discovered its plagued with the dreaded drifting whilst trying to yaw. Have flown it 10 times now over the last three days in everything from a 15mph gusty wind to dead calm conditions but the drifting occurs in all conditions and can be as much as 20ft. Doesn't seem to make a difference if I yaw quickly or slowly - off it goes on a wander around the sky & then, automatically, it goes back to the postion where I started the yaw. I've tried an advanced IMU calibration on perfectly level ground but it didn't help. I braved removing the lid of the quad to check the NAZAM unit is correctly seated but it looks fine - solidly mounted and dead level. I've read a lot about re-setting the compass but I haven't tried that because in Attitude mode it yaws perfectly true & as I understand it in Atti mode only the GPS lock is disabled but both the compass & barometric systems are still used. In terms of GPS, I'm only getting between 7 and 9 satellites but even with 9 & no wind the problem persists. In all other respects the phantom flies perfectly. The Phantom shipped with V3.09 firmware but I upgraded it to V3.12 before my first flight - is there anyway of going back to V3.09 or does anybody have any other ideas for a fix or should I send it back to DJI??