In our household, it is known as the horny honk. It's a wheezy sort of noise that kind escalates to sounding like a chew toy. Jimmy can get pretty loud sometimes, but seems to cool off pretty quickly too.
If you pay attention to what is going on when your pi makes this noise, you can maybe adjust things so she can cool off a bit. For Jimmy, usually it's when she gets under a toy and has it rubbing her back. I just move the toy away from the side of the cage or higher off the perch.