First of all, I got my quad flying without any problems. And man... I'm so excited, this is the base for my AP platform.
But during the last flights I noticed two seperate wobbles during a 10 min flight. It seems to start with one engine and then it wobbles in a circular movement. I don't really have a good idea what could be causing the wobbles, so I hope you (more experienced) multicopter pilots can help me out.
I have experienced that when I had too heavy of a payload. I call it the "warble spiral of death". I am now in the process of bulding a platform that is three times the size.
You will probably find it has something to do with the PID settings?
What do you have for Rate I?