yes.
is she only falling when you are within eyesight?
if so, its probably what i call the suicide drop.
she wants to get away from you as fast as possible, so she lets go.
I know exactly what you mean.....but no. At first we would be I'n the other room and hear her fall (now we have a pillow covered by a towel at the bottom of the cage to break her fall). Sometimes we come into the room and she's hanging by one leg and her tail from a branch...... This has been happening for a couple weeks now