"Did you change the chanel mapping for the MX 20? You must change some channels to so that they fit to the APM: CH 1: Roll Left = low PWM – Roll Right = High PWM CH 2: Pitch Forward = low PWM – Pitch Back = High PWM CH 3: Low Throttle =…"

"You don't need any bridge on the APM2.5. Remove it and should work"

"This apparently happens when ESC's don't think the throttle is "off".   I had one motor beeping on my hexacopter; it turns out that the ESC's are not "calibrated" the same (and vary by temperature; only…"

"Joerg, I had a similar problem and I second what Richard said. You may want to follow the instructions for calibrating the ESCs one at a time. That was the only thing that worked for me. Jason"

"Try calibrating your ESCs. Your motors should never spin unless you are running a motor test from the CLI, which spins 1 motor at a time slowly or only after arming and then they should all spin with the throttle input."

"I have recently changed from this 3S 2650 LiPo 2212 1000kv motors 20A ESCs 10 4.7 props Got everything tuned and flying beautifully in Stabilise and Alt hold(loiter,position). My flight times were less than desireble so I went to this: 4S…"

"jjohow,      Yes, i agree with robert.  if you're talking about it shooting up when you're in stabilize mode then you should adjust the THR_MID value.  So for example if your copter hovers as 35% of throttle…"

"Wrong forum, but I think what you want it to adjust THR_MID."

"Great I'll try it! Thank you very much for your help!! Joerg"

"Hi, You need to include logs that have RAW and INAV turned on. Then we might be able to help."

"Have you performed also the ESC calibration? By the radio calibration, have you already checked if the low-high PWM are in the corect sense? Maybe you need to use the servo reverse on your transmitter. "

"Hi Darren, thanks for your answer. I tried calibration 3 more times with no success."

"It kind of sounds like the esc's are in programming mode instead of arming. That happens when the throttle isnt low enough in order to arm the esc's. (so they go into programming mode automaticly, and uses the throttle position…"