I am thinking that he is as loud as he is partially because he is wanting you to hear him over the TV, just as he would in a flock.
He doesn't get nearly enough out of cage time either one on one with you or as free time to fly about, explore or just to hang out with you. He really needs to spend at least an hour each day one on one with you and at least another 3 to 4 hours out of his cage to do what he needs to do, probably just to hang out with you. I think that his getting as loud as he does is him trying to talk with you as he wants to spend time with you . Try giving him more time out and see if that helps. You could get him to quiet down when he does this with the TV on and when he does quiet down let him out to perch on your arm or shoulder and spend time with you.
Let me know if this helps.