Quadcopter auto yaw issue

I am using pixhawk cube orange with AC 4.01. I am building an agricultural spray drone . I am facing issue of copter continue to rotate anticlockwise. When i reviewed the log, RCOU C4 is running very slow. In order to compensate the speed RCOU C3 is running very fast.
Please suggest and help me out

Motor mounts are twisted, or frame flexes badly…
Either that or the motor spin directions are wrong and the wrong props are fitted to them.

Upgrade to latest stable before anything else, currently 4.1.1

Thanks. Will check the suggestion you provided

Whether there is interference from high current near pixhawk cube orange