I have a Symphonic TV and I plug the cable line directly into the back of the TV. There are only certain channels for some reason that have a solid black recctangle box that comes up only when the main program is being shown, not during commercials. All these channels are channels that I do get in my Time Warner Cable package. I get this through my landlord, so I cannot contact time warner myself. Any ideas as to why this happens and a way to some how stop this?

Sounds like you are getting the name of the channels blocked off. I'm confused why you can't contact time warner and have it checked out? They need to determine if it the line or the TV.

Is the size of the square PIP size or channel number size?

The box takes up about half the screen...

Do you have PIP or Split screen?

Im sorry I guess I am not sure what you mean by a PIP screen?

Picture in Picture.
View 2 video sources at once.

Oh then it would be a split screen...