I found the follows
1. Using the table below find your make of TV and the code which matches it.
2. Press and hold down Volume + and mute on your remote control at the same time for at least three seconds, until the green light in the top right-hand corner of your remote control flashes twice.
3. Release the buttons and enter the first four digit code from the table below. (You must do this within ten seconds).
4. As you enter the first three digits the green light on your remote control will give a short blink.
5. As you enter the fourth digit, the green light will flash twice to confirm that the volume is set.
If setting the volume is not successful, please repeat the above steps with the second or third codes from the table below.
http://www.virginmedia.com/help/documents/VRem oteControlVolumeCodes.pdf