VTOL(4+1) Unequally distribution of PWM output

Hi, It’s my first post here. I started using the program only recently as for my new work, so my knowledge of the program is very low.

The first fight test was a hover test for the plane, the plane was set up and config following all the tutorial, we encounter a problem as the plane started to hover but a bit after hover, the plane started to yaw without any input from the radio transmitter. The plane is on Qstabilize the whole flght test. After a couple more try, we saw the problem as the motor setup (PWM output) in the servo output haven’t been distributed or didn’t go up equally across 4 motor.

We come back to test it more without connecting the ESC and motor connected to the pixhawk orange cube, but the result came back the same way, the only different is the output for each corresponding motor we saw at the first flight test went to the other at random every time we try to re-config the pixhawk.

We tested the fixed wing part of the plane the same way (without the ESC or motor), but the result came back just fine. Is there a way to fixed this problem? no one that we know have encounter this problem before.

Flight test
[VTOL Problem - YouTube]
(VTOL Problem - YouTube)

Servo output monitor
[PWM signal output - YouTube]
(PWM signal output - YouTube)

The problem got us on the wits end here, so we tried to rework the whole parameter and start trimming the motor which help a little. Then we rework on the whole electronic system with a speculation of maybe the power input to the motor is not enough and it help quite a lot, but unfortunately Our plane still sliping and has a power cut after a little of throttle decrease. We think that it might have to do with the EKF_Lane _switch to compass, so we are working on it right at the moment.