Originally Posted by melilla
Hi I have a mega flyduino v2, with FreeImu 4.3, gps FM4.
When I connect the battery sometimes the esc are ringing at intervals of one second, and the motors are not activated
Sounds like the ESCs aren't calibrated properly. Try to calibrate them one-by-one and set the endpoints of yaw/throttle on your transmitter.
btw: which firmware are you using?