I have built 5 quads using the CC3D controller. They oscillate a lot in flight and one even flips over on take off. I have used Open Flight and Libre Flight with the same results. I have not changed the PID settings from the default. Any ideas what I might try?
It would make it easier if you emailed me directly at [email protected]. I am trying to reduce vibration to the board but it still is not right.

This is the best PID tuning video I have seen. Easy to follow. I use the cc3d and it definitely needs tuning from the defaults. Hope this helps.

For the one that flips over on take-off: check board- or sensor-orientation, motor order. If those are correct, try to increase min_throttle (or digital idle if using dshot).

In case you are using sensor-orientation, be aware that "default" does not mean zero degrees on the cc3d.