Flashes on the Telly

Hi I have a LVW5005

The problem is a bar which is dark running across the screen which upon reaching the left as you look at the image makes the whole screen get brighter and drops back when it starts from the other side again (most evident in the menu system of the old ITV digital box because of the bright orange background.

this comes from all sources and if the unit is put in standby it disapears all together. I have tried different cables including the one supplied and this has made no difference.

any ideas would be helpful

using firmware 0098 (but won’t let drive update )