I have a Syma X8C. I have done the calibration as described in the manual. Controls don't respond as expected, even in headless mode. So forward is not forward and quad goes right, and so on. Props are all installed correctly. Is there a compass calibration that can be done, other than the simple horizontal cal in the book? If I was in normal flight mode I can understand that I might have front and back confused, but in headless mode that's not supposed to happen. Right is right and left is left, no matter the craft's orientation. Any help? Thanks