Well, clipped birds feel terribly insecure and that makes them scream more than flighted birds (a bird that does not feel comfortable in a given situation can take off but a clipped bird has no choice but to remain and that causes stress which, in a baby, will prompt calls for help). Is the cage the kind that has a dome top or a flat one? I find that birds hugely prefer the kind with the flat top.
As to her biting if you ask her to step up to your hand... well, well-raised babies never bite and it's not only because they are well-raised but also because they are babies. Prey animals are not born with an aggression gene, they need to learn to be aggressive and it's always people who teach them so, unless she was not properly socialized by the breeder, she should not even try to bluff a bite (macaws are big bluffers). BUT, if you don't feel 100% safe using your hand, use a stick.
People always talk about their birds biting or nipping when their owners ask them to step up but, in my personal experience and opinion, this happens because 95% of the time the birds do not spend enough time out-of-cage and the owners ask them to step up just to put them back in their cages - which they do NOT like (and who can blame them?). Parrots are VERY intelligent and put two and two together... Do you play with her? Do you allow her to ride your shoulder while you do things around the house? Does she have a box on the floor where there are a lot of toys and chewies for her to riffle through? They don't have to be parrot toys, you can put all sorts of 'attractive' things in there... little cardboard boxes, crumpled up paper, medallions of dried yucca, pieces of untreated pine 2x4, balls of different sizes, big knots of untreated sisal rope, coconut shells (wash them thoroughly first), natural pine cones, etc. You need to put, at the very least, 4 hours of one-on-one and, although that does not mean you need to spend 4 hours paying attention to her and nothing else, it does mean 2 hours of that (you can sit on the floor and take things out of the box for her to look at and study, you can dance with her, you can play a game of 'find the ball' only make it a nut under the cup, play with an interactive baby toy -like the ones that have music or animal sounds or the ones that look like an abacus with beads running on thick wires, etc.) and another 2 of doing your thing but with her on your arm or shoulder or right next to you so you can interact with her. Baby parrots (and adults, too) require an inordinate amount of time spent with them and a lot of work and thought put into it. If dogs are a 3 in a scale of 1 to 10 maintenance requirements and cats are a 1, adult parrots, especially the large species, are a solid 10 because they are super high maintenance in terms of human effort and require 6 hours every single day of their lives of attention, interaction and direct supervision. So prepare yourself for the next 60 years of slavery to a parrot