Truncated picture problem

[babayaga]

Hi, I've been having a problem with my T.V. picture for some time, not sure how long.
The picture on my TV is missing a slice at either side, so the start of any words miss a couple of letters and the end is the same.
I tried resetting it and changing the picture setting to widescreen from 4:3 and back without any result. I know it isn't my TV because pre-recorded DVDs are O.K.
I've taken out the scart lead and put it back but also to no avail in fact it seems to have taken a slice out of the top and bottom as well. I did notice that the connector on the scart lead is slightly bent. Do I need a new one? I'm not very good with technical stuff, so need simple instructions.
Can anyone help?
My set top box is a Pace.

[BenMcr]

If the picture is being cut it sounds like it's set to 4:3 on the the STB

If you have a Square CRT TV then you need to set it to Letterbox. If you have a Widescreen TV then set it to Widescreen