Servo jitter

[Swagg93mixon]

So I just build my 2nd mini arrow. I flew it today for first time it flies like a dream even better then my first version however I noticed while checking my craft that when I accelerated the throttle past 50% my left servo would shake and end up at full up deflection is this just a bad servo or could something else be wrong

 

[Swagg93mixon]

Here’s a pic of it

 

[Bricks]

Might need a little more information type of radio receiver servos battery being used, other wise like reading in the dark closet ain`t going to happen..

 

[Merv]

Hard to tell from the picture. I could not see any control rods or control horns.
Are you saying the servo goes full up while bench testing?