I would agree with Talon that maybe something has changed that they are unhappy about, or they want more out of cage time with you. Is there something new outside the big aviary that is upsetting them? Mine usually causes a racket when I put him back in his cage sooner than he wants to go, or if my dogs get very hyper sometimes this causes him to get hyper too and he wants out to join in the fun. I think really the only way to deal with it is to ignore them, even though it is so hard. Greys do best with positive reinforcement- reward them for being good and doing what you want- but ignore behavior you do not want to encourage.
As far as the whole terrible twos thing goes- it probably varies with each bird I would guess. Mine who will be two in another month has a very onery streak where he wants to do what he wants to do and he kind of throws a fit if he doesn't get to. For instance, he likes to land on the lamp shades in my living room. I take him off and put him back on top of his cage and he flies right back over. Eventually he keeps doing it and I have to put him back in his cage and he either tries to bite me when I go to pick him up or flies away before I can get him in the cage- or once he is in there he squawks repeatly to let me know he isn't happy about it. It will take a lot of patience for me to get through this with him but I have faith we can do it! Good luck to you!