Flickering gamestate after locking


I'm calling lock() (in the openGL thread) on the rootNode of 1 gamestate. However this results in flickering of objects in another gamestate, it looks like he cant decide whether the side of a cube is in the light or in the shadow and therefore keeps switching between light and dark.

This flickering is not allways visible but seems to be depending on the distance and angle from the camera to the object.

The flickering was never there until i called lock.

Any ideas why locking in 1 gamestate affects another gamestate ?