Multicopter crash after changing from RTL to Stablilize, also from Stabilize to Postion mode

My team and I recently had a crash after changing flight modes from RTL to Stabilize and we also had another crash after switching from Stabilize to Hold. We are not sure that the crash is due to the switch in mode, however, we suspect that the crash occurs whenever we switch from an auto mode to a manual mode or vice versa.

Information about the drone:

  • Quadcopter F450 Flamewheel
    -Pixhawk flight controller
    -PX4 version 1.9.1

The flight logs from the crash:
Stabilize to Position:

RTL to Stabilize:

When reviewing the logs we’ve noticed that the roll angle jumps suddenly after switching the modes, this also is reflected in the actuator outputs. We suspect that this might be the reason behind the crash but we are not sure.

We tested the drone before, and the drone was fine and did not show and any instability or crashes. A few weeks later we started facing these issues.

The first flight we took off in stabilize and tried to switch to position mode and we crashed almost immediately after switching the modes.

Next, we took off in position mode and there was a geofence setup and the action was RTL. The drone switched to RTL (due to geofence violation) and went back to its starting location. The RTL settings were set to Loiter and do not land which the drone did successfully. However, when we switched to Stabilize mode to regain control the drone crashed again.

If anyone can help us with this issue it will be really appreciated.

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