try this:
Check the tv volume and the cable tv volume.
When you set up your wii there is 3 cords, red white yellow, make sure all of them are plugged in.
If it still doesn't work the turn off your wii and turn on the actual tv and if you still can't hear it then the tv is broken
It might not be broken, look at the tv remote for a button that says something like "mute" and press that
