Going crazy. I'm in the process of building a new quadcopter. I am using a pixhawk PX4 flight controller. Everything went fine with the setup but after arming it, the motor's did not spin nor did the ESC's make any noise. Spent about 3 to 4 hours going over it and am completely stumped. I calibrated the ESC s using the receiver with no problem so I know the motors and ESC function. Don't know where I went wrong. Help!