Vibrations coming in yaw

hi i am using px4 for the quadcopter i am building, there is twitchy sound coming when i fly it for sometime huge vibrations are coming as well.
could anyone help ?
Link :

I tried finding out but the only thing i came to know is that on that twitchy sound the esc switching is taking place. I have attached the actuator output graph in which the rapid switching take place at that particular point.