I have an mRo Pixhawk x21 with a Holybro Ublox GPS module.
It has worked great running copter on a DJI f450.
At some point I switched to ardurover 4.0 for a boat project, and have since been experiencing the following when connected to mission planner:
Compass is off by about roughly 100 degrees. i.e., when Pixhawk is pointed north, compass shows about 260. Compass and accelerometer were successfully calibrated multiple times
While board orientation is standard, the pitch and roll axes are reversed, meaning pitch motion causes roll and roll motion causes pitch. Yaw seems ok.
Getting ‘unhealthy ahrs’ warning. GPS lock is good.
I tried switching back to the latest copter release, reinstalling mission planner, resetting Pixhawk and reloading firmware multiple times, but problem persists.