It is much easier to stop it from developing than to stop it once it is an ingrained problem. Parrots love to scream and make noise. They live in huge flocks and talk to one another constantly and loudly! It will take great patience to get your bird to be quiet. You will have to allow it some noise and for the rest, well, you can't discipline or cover the bird. First off you need to understand why your parrot is screaming and why it stops when you return. Parrots live together in flocks, that one of their protection solutions. They feel safe in numbers. When you leave, it's alone. It's not screaming for attention but for contact. When you leave, what often happens is they will call quietly at first, asking where you are going and they get no response. So they call louder, and sometimes a person may yell back. They learn that when they scream, people answer back and they feel they have made contact with their 'flock'. Each scream from the bird is a contact call with you. If you come back in the room, there is no need to make the call anymore. Some people say to ignore it, but that usually does nothing to make the bird feel safer or protected. It's still a bird in search of his flock. It may scream even louder. If you ignore it, it may develop other insecurities and get very unhealthy and unhappy. What you will need to do is reassure it when you leave. You may need to tell the bird whenever you are going to leave the room, even for a minute. If it calls, use some phrase to say you are leaving. Then when you get back, greet the bird to make sure it knows you are there. It needs to associate you with your own 'contact call'. Never scream back at it. Just make your contact as soon as you enter the room and rally give it eye to eye contact. If they bird screams and you come back, give it your contact call and wait until it calms but don't give it more attention. Don't reward bad behavior. If it starts playing or eating, something positive, reward THAT behavior and tell him you're so pleased with him. What a good bird!!! Then try telling the bird you are leaving and go again. Yes, it won't be easy since he's already picked up the bad habit, but if you are persistent and reward the good, he'll learn that a contact call means you are still around and he's to patiently wait for your return. EDIT: I wish people would explain why they don't like an answer. So why the -1 for a good helpful answer? Why don't you teach us something and say why the downrate?

Thats a sun conure for you. To start with, buy ear plugs. Next, don't discipline your sun conure in ANY way until you know the reason for the screaming. Although suns are a naturally noisy bird, they're very intelligent & can learn to communicate in a quieter way. They also usually only continually scream if there is a problem. You need to know what this problem is. Most of the time it is needing more attention than it's getting. Suns are very high on the list of extremely needy & clingy birds.They're never afraid to let you know if they're missing out or if something is wrong. If you discipline the bird by putting it in the cage or covering it every time it screams & you don't know the reason for the screams you can make things worse. Given the right amount of attention, a play gym or large cage with chew toys & positive reinforcement will give you a quieter bird. I have a re homed 5 year old sun conure who also made our ears bleed but she's now the quietest bird in the house. A happy sun conure is a quiet one. Also look at the age of the bird. If it's still quite young & still at the learning phase in your home, the screaming can be testing you to see what it can get away with or if it's getting attention every time it screams, even if it's just a glare form the distance, this is teaching your sun to scream to get attention.