I have built an octo which rolls to port on takeoff. I have checked the forums and can confirm;
1) ESCs calibrated.
2) ESC wiring checked ( Motor test)
3) All props have been checked for left/right hand
4) Have calibrated accelerometer 3 times.
5) Roll says 0.21 when sitting level
6) Have swapped motors from left to right
When I hold it and throttle up and let it lift off the ground it fights until it is sitting at an angle and then is happy. Of course it would fly off to the left if I wasn't holding it, but very little force is required to stabilise it. If I try and level it in the air, it fights.
I only have an old 3S battery which is why the voltage drops so quickly under test.
Any help appreciated.