Does anyone know about digital converters for a TV box set?

Question

So I just installed a digital converter to my T.V. and its works fine, I get both clear sound and picture. But there are some channels where I get the picture, but no sound. Do you how to change the options so I can get sound on those channels?

Answer 1

Is not the box is your tv antenna. Because in my box some channels are black and my dad says is the antenna so we are buying a new one. :D