I have been getting very smooth very nice video from my homebuilt quadcopter (http://flitetest.com/articles/large-scratch-built-quad-copter-aerial-photography) 2 axis SimpleBGC gimbal and Xiaomi Yi camera EXCEPT that the horizon tilts whenever I yaw in either direction. I have installed the SimpleBGC GUI v2.2b2 and it works fine, allowing me to make changes to the gimbal controller settings. I have not been able to figure out how to stop the horizon from tilting with yaw. I have channels set up to alter Pitch and Roll settings with my radio....nice to change the look down angle. I can correct the out-of-level horizon this way, but I shouldn't have to correct and I would prefer not to have to correct. It interferes with the overall smooth video stream. I have search online, and found that many others have had the same problem. Can anyone tell me how to make the horizon remain level when I yaw?