Sound is sent separate to picture's so it is more then likely your signal.Even if you do have a very strong singal dish still mite need to be realined,
OK if you want to update the software on your Digibox,
This is what you do.
1,Remove power lead from back of the the box.
2,Press and hold down the backup button on the the box its self.
3,While holding down the back up button plug back in the power lead on the back of the digibox while still holding down the back up button.
4,Now about 20 secs in all the lights will light up on the front of the box and should get a message on screen to say the box is now downloading the latest software update.
Some boxes mite not give a message on screen but if all the lights are light up on the front of the box then it is downloading.
5,Now u can let go of the back up button on the digibox.
It will contuine to download,
New software mite help your sound problem,
It also mite speed up your EPG,add new menus and services.!!
**Warning do not interrupt your box when it's downloading new software!!