Random motor not working while holding the copter down

Hi, noob pixhawk user here. I got pixhawk 2.4.8 to run f550 drone scheme. We got 6 DJI 2212 Motors. The problem i got is not solvable, I tried every option on the internet. The problem is we have some kind of control issue, when we try to lift off, one random motor decide to not work, or work slow. We couldn’t find any way to fix it. I’m attaching a video and parameters we used. Thanks in advance.

parametre.param (16.8 KB)

You are holding the copter down. And converting a closed loop control system into an open loop controll system

The test is invalid. Do not test it like this. look for all the threads on this forum explaining why this test is invalid.

We are holding copter down because if we are not copter just turns upside down. We are not testing motor, motor testing works just fine. We have this issue only while taking off. That’s why we are holding down the copter.

If the copter flips on takeoff, the motor order or rotation direction is wrong. Correct it please.

Use the motor test function in Mission Planner. Check that you have the motors spinning in the right direction and that the minimum and arming speeds are correct.

And take the props off so your friend won’t lose the ability to count to 10.

A dangerous and useless test.