I must be a moron because I cannot get ESC calibration to work using the “Calibrate ESC” function in Mission Planner (“Normal” ESC mode). Nor can I get it to work using the “all at once” instructions (the LEDs never flash as illustrated in the video). My ESCs are the “old-fashioned” power up with radio throttle at max and wait for ‘music’, reduce to minimum and wait for different ‘music’ and you’re done" analog version. Connected to a servo simulator I get the tones, but I can’t use that calibration on a different driver, obviously. No matter what I do I can’t get the expected tones out of the ESCs hooked up to my Pixhawk 6C. Most of the time when I press the safety switch I get a continuous rapid beeping, which I assume is signaling an error condition, though the documentation that came with the ESCs makes no mention of such a beeping pattern. Sometimes after going through what appears to be an unsuccessful calibration (no musical tones at all, simple evenly timed one-pitch beeps), the motors will silence when I press the button. When that happens I can go to the motor test section and the motors will spin–at different speeds, so clearly the calibration didn’t actually work. Since the motors SOMETIMES work more or less as expected, I am confident the electrical hookup is correct. I have done the radio calibration and the throttle channel performs as expected. There is no way will even begin to trust this autopilot if the motors spin at different speeds while testing.