Ive been working on my first custom built quad copter using an arduino and im having problems with 2 of my esc's. i connect them to the battery and motor but i can barely hear the beeps and after calbrating it i can slightly hear a current going through the motor but its very small. i checked the voltage output of the esc using voltmeter but it barely picked up any voltage but once the motor was removed the volt would spike just like it should when it makes the motor beep. the other 2 esc's work fine and they are the same type as the other 2 that arent. does anyone know how to fix this or if i need to get a new esc's? my specs are.

11.1V 3s lipo battery 
20amp 6-16.8V esc
1000kV motor