Motor speed disparity


Ive noticed that motors 1 and 2 spin considerably slower than 3 and 4.

1 is front right
2 is back left
3 is front left
4 is back right

The mystery is why aren’t I spinning? Yes, I checked motor alignment, they are vertical. Yaw control is good, but I can tell there is a considerable speed disparity, especially when yawing in one direction.
When loitering, motor ch out shows 1400 for 1 and 2, 1600 for 3 and 4 so it is not ESC calibration.
When I arm all ch out are 1205. When I give a tiny bit of throttle far away from lifting it already starts giving more to 3,4. Why?
I did accel calib again, same result.

gyro status “gz” looks ok to me.
Flight is great but I don’t like that motors 3 and 4 do all the work.
Please help me find out if it is some kind of gyro issue.

frame: X quad
6S, 390kv, 15x5.2 props
MTOW: 2500g