Hi bjblackmore & Welcome.
Demand that you require a new STB, I have had the STB replaced three times during my custom with ntl. Which in one particular time the engineer came & replaced a broken STB with a broken STB while he was there, so he had to go out in his van and pick up another.
There is a way out of your contract soon, if and when ntl raise the prices of their ntl DTV product.