Here are two videos of us trying to get our baby to fly:
We have HK-SS20A ESCs and KDA-20-22L motors. We suspect pretty bad PID settings and we will continue to keep trying to fix the problem by tweaking the PID settings. But we wanted to know if any of you had any other ideas of what may be going wrong. Jani Hirvinen suggested that our ESCs might be of different kinds even though they are advertised as being the same or something may be wrong with them. But upon changing the connections of the control lines from the receiver to the APM the two motors that were running slower and causing the oscillations changed to another pair of motors. Also we have checked our ESC calibrations and that the motors are rotating in the correct direction. Any help would be greatly appreciated.