Copter wandering with 3.4.4

Hi all,

Today I went out for a quick flight test of my quad and it was really unstable in loiter. It was wandering ocassionally 2 meters off the loiter point. Not much wind, just a slight breeze sometimes.

Position innovations in EKF seems like a sawtooth. Seems bad.

Any ideas are more than welcomed!

Log:
https://drive.google.com/open?id=0BzRzbaLTcOpbSWRIQkg1aGMzSGs