what is this noise?

[Imveganbtw]

Recently my bird has been making the growling noise at me when I get near her or change something in the cage. What does it mean?

 

[Rozalka]

I call this sound as "crying" because Rozalka makes it when something happens she doesn't like. But I'm not sure what it may mean in this case - because you say she wasn't doing it earlier? With changes, maybe she just doesn't like them