[mporlier]

Check your clutch, maybe slipping or your piston ring is damaged. OS is know for this. Clogged fuel line? Air getting in the fuel line...

Oh! Sorry you have an electric, none of those things can happen... Lucky you :-)

I would disconnect the rods leadings to your servo and move manually the swash. Move it up and down on the main shaft. Mine got tight and drained my battery super fast. I needed to clean the main shaft and change the swash (went with Quick UK).