Answer by
LeheckaG (1826)
A "black rectangle" in the middle of your TV screen,
sounds like you have "Closed caption" text decoding
turned ON your television, recorder, or cable/digital-converter/satellite-decoder box,
but not set to the appropriate mode/parameters.
Starting with your-television,
go into its owner's-manual, or set-up-menu and scroll-through the sub-menus
looking for "Closed-Caption" options.
If not on your television, try your-recorder or converter/decoder-box.