Autotune results in very wobbly copter

I have a tarot 250 with a pixhawk lite controlling it, but I can’t seem to get the tuning right.
Using 6x3 HQ props with DYS 1806 2300kv motors autotune will run just fine for each axis.

The result is very good for quick movements like those twitches while autotune is running. But as soon as I start to fly forward and keep the copter at an angle, it will wobble like crazy up and down once a second. The behaviour is consistant for stabilize, alt hold and acro mode.

I’m not sure if there are any problems with vibration or any sensors and it would be great if someone could have a look at these two logs.
drive.google.com/file/d/0B6dJjd … sp=sharing
drive.google.com/file/d/0B6dJjd … sp=sharing

Any suggestions how to get autotune to get it right or what to adjust manually to fix this wobbling?