ThirdPersonController/ThirdPersonAnimatorController Jitter when moving

When using the ThirdPersonController I get jittery movement. This issue is present even using a vanilla ThirdPersonController with the Ethan avatar out of Standard Assets. Even just moving in a straight line the movement is really jittery. Whilst this is a problem, on its own it is not a huge issue. What is a huge issue however is if I set a camera to LookAt the character then when moving about it shakes the camera around even if I use the LookatTarget script in StandardAssets.

I don't know if I'm doing anything wrong, I don't think so. Does everyone get the same as me? If so I'll implement (or find) a method for smoothing the camera's movement, i know there is a SmoothFollow script, but I want a smooth look at script.

UPDATE

So I created a script to smooth the camera movement, it basically sets the velocity of the camera proportional to the square of the offset between the last position and the target position and this works perfectly for the camera. The camera now moves smoothly through the scene relative to the scenery. However... Ethan is having a little trouble as he jerks and twitches his way through the scene.

So the real question I suppose is... Why is the ThirdPersonController creating jerky movement on the Ethan (or any other) avatar?

Please note that the animations themselves are smooth, it is the (root?) position of the avatar that is shaking about.

UPDATE 2

I think that the issue is coming from the ThirdPersonAnimatorController . I just wrote my own version of ThirdPersonController (I wanted to do this anyway) but it still uses the ThirdPersonAnimatorController to control the animations. And I still get the jittery motion. I will begin looking into the ThirdPersonAnimatorController code as I intended to rewrite this anyway...