I`v had a problem since buying my new APM 2.5, the ESCs beep every 2 seconds.  This shows an abnormal output.  I have tried calibrating the ESCs and reloading the firmware 20 time and still no joy. I have just tested the output with an ociliscope and found there is no output signal.  I tested the output from the RC reciever first and thought I should get a similar square wave pattern.  Unfortunat…