Drone unstability with Cube Black

Hello All,
I have 3 identical drones heavy pay-loaded. Two of the are flying well. But the third is still oscillating and is not stable. I changed params, changed Pixhawk, but in the Auto Analysis I have still report about the slow loops. It is desperate situation. I dont know what else I can do to repair this unstability. Could you somebody help me?
Many thank. Log is included.


G

You will need to measure , reduce vibrations and tune the PID loops.
There is documentation on how to do this on the wiki.

Thanks. I will do.
G