[JensR]

Edit: Just saw that you already run a receiver pack. Unless this is very weak, my following text won't apply to you.


If you are relying on the ESC's BEC and your servos draw a lot of current, the BEC might break down, which shuts off the receiver and hence the servos' current draw. Then, the system comes back to life, with the control stick at whatever position it was and the self-learning ESC takes this as the new neutral.

So maybe, all you need is a stronger external BEC?

I use 5 cells of my 12V pack (it's actually a double 6V pack) to power my receiver. Not ideal, but enough grunt.

Cheers
Jens