We are experiencing a weird issue where whenever we switch our plane into fly by wire A mode, the plane immediately starts diving. We have had this happen on two separate flights, and I've attached videos of both of these flights as well as the data flash log. Looking at the logs we noticed a couple of oddities.
1. The RCIN and RCOUT for channel 3 does not match up, even when flying in manual mode. We believe this is due to an issue with our radio calibration, but we don't think that it would cause the pronounced drop off when switching into fly by wire A or Autotune.
2. As soon as we switch into fly by wire A or autotune, the pitch immediately dives and the desired pitch rises to compensate. Howver this does not appear to have any affect on the actual pitch of the plane.
Physically, we think our plane is mostly fine. It flys well in manual mode, and although our pilot noted a downward and leftwards tendency in the plane we don't think that this explains the drastic downwards pitch in fly by wire A mode.
Does anyone have any experience with a similar issue? Thanks for any help.
Videos and logs of the flights (too large to attach)