Altitude glitch on Holybro Pixhawk V4 (fmuV5) with CUAV 5 Copter 3.6.5

Hello every body,

I’m facing a problem of altitude.
Today I made a test fligth with the goal of testing security processes.

For the first flight I tried to maka an automatic RTL + landing. For that I put a RTL Height to 10m.

When I went to RTL, the drone climb very hight, come home and land as expected except for the height of RTL.
BIN log can be found here : https://drive.google.com/open?id=1SjkAkXndEDj_QVN_Cja5VKrkMymTpXPC

Then, at home, I analysed the logs. They saw some strange values for height of flight.

At home, on the kitchen table, the altitude is glitching continiously, going down and down… Sometimes, it cames to 0m and the going down and down again!

I put a video on Youtube that shows the problem :
https://www.youtube.com/watch?v=LXXBcDSjLDQ

The drone an hexacopter with a Holybro Pixhawk V4 and Ardupilot 3.4.5

Any ideas of the problem?

OK, It seems it’s an hardware issue.
I’ve changed the flight controller with a identical model and copied the configuration.
Every thing seems fine now.