Need Help Tuning

Hey guys, I’m flying an ISO Aeritech and am running it with a Pixhawk.

I’ve been working on getting it tuned and I’m happy with the roll tuning but I’m having some weird behaviour right after switching to auto with yaw oscillations. I fixed them initially with a slight increase in yaw damping but the problem returned again after a few days.

I don’t think my airspeed sensor is calibrated well, Could you have a look at the logs and let me know if anything else is off and suggest changes?

The first log is of a decent flight which needed work on the pitch tuning. The second one is where the yaw oscillations returned.

https://drive.google.com/file/d/0B3b7WrkCZNG4Vy1iUEtiNmd0QlE/view?usp=sharing

https://drive.google.com/file/d/0B3b7WrkCZNG4ODViYzZaenYzTUk/view?usp=sharing