make sure that the coax connections of your gateway, the main TV box, and this box are fully tight. Try unplugging both this box and the main box for 30 seconds and plug them back in. If that doesnt work, Look and see if there is a cable amp in your house, it could be in the basement, outside in a box, or in any other place. If there is one, make sure it is getting power, there should be a light on it. If it still doesnt work you might need to replace the box.