Thank you for using Just Answer.
We will need more information to answer your question best.
What is the model number of your TV? It's on the back of the TV on a sticker.
What kind of cable are you using to hookup from the HD Direct TV box to the TV (HDMI
, component which is red,green,blue, composite which is yellow or a 75 ohm calbe which is round and screws on)?
What channel are you tuned to when the TV shows 480?
Who did this hookup and how long has this hookup been there?
So that we do not repeat what you have already tried, what have you already tried to fix this?
Thank you for your patience.