Two possibilities. Check to see where the "offset" is set (the controls
that let you position the image on the screen). Also check to see
where the "display" setting is -- automatic, dot-by-dot, full screen,
4:3, etc.

Is this a *service* setting? Or, a *customer* setting?
(IIRC, I don't recall seeing anything that looked more
sophisticated than typical TV controls.)

These are customer settings. There might also be service settings that
apply.

My suggestion is a guess -- there might not be anything thing wrong with the
set other than misadjustment.