Whats different about the previous home vs your home? Do you think that the lack of flock mates (i.e. other birds) could have anything to do with it?
Sometimes, ignoring the screaming is only making it worse. Your bird screams for 5 minutes. The bird calms down for 1 minute. You go in and reward the bird. The next time the bird screams, it might scream for 8 minutes. After the bird calms down, you go in and reward. The time after that, the bird screams for 15 minutes. After the bird clams down, you go in and reward. What are you teaching the bird to do? Scream.
I've posted this before, so I'll post it again... please, read it!
Living With Parrots Cage Free: Does Ignoring Really Work?
I'm just saying that ignoring it doesn't always work!
What I do suggest is allowing Charlie to fly. If he's clipped, then see if he'd be willing to allow you to run him around the house encouraging him to fly or teaching him to hop to you on command. Maybe swing him around! [My] Charlie loves it when I swing him! I don't have a video of it, but I know another mitred conure who also loves it! Except Ditto seems to get into it much more than Charlie does!
[ame="http://www.youtube.com/watch?v=ZfE2m1w2oDE"]Playful Mitred Conure - YouTube[/ame]
Get [your] Charlie a harness! Take him outside on short 20-30 minute walks! Maybe when he's out there, encourage him to scream! That way, it's not quite so painful in your ear or anyone elses and it'll help him get rid of some pent up energy!
[ame=http://www.youtube.com/watch?v=13XmlniLKd4]Charlie Flying Outside - YouTube[/ame]