EKF Longitude value high variation with accurate GPS

ArduCopter Copter 3.5
1

Hello,

I’m currently facing an issue and I’ve no idea how to fix it.

Drone is on ground GPS has a 3d-fix, but EKF longitude is oscillating towards the GPS longitude (note that it also happens with latitude only or both), logs confirm that GPS is more than stable.

I’m having this issue 3/4 times for 10 power up.

I’ve the same problem with EKF2 or EKF3, tested on 3 pix4, all on 3.5.5, changing cables for power supply (always powered from the pix4 power module).

I’m convinced that its not an hardware issue (or I am the unluckiest man on earth to get 3 hardware with the exact same problem).

Note that when the problem doesn’t show up I can fly smoothly (cable connection problem should appear in flight too, so I can remove that from the equation).

screenshot

I’ve included logs

thank you for your time :slight_smile:

2

Still didn’t manage to get rid of this problem.

It happen far less with ekf3, if it helps.