Pace box problem

[shibby]

ok i got a pace 4000 box i think.
i've got a problem after a week it will lose the picture i have the now and next but it will only say what was on hours ago.
this has been happening for a few months now, the box is not blocked by anything it sits on a shelf of a unit that is not closed.

this is a refurb boxed i got early last year. it was a replaceing for a box doing the same sort of problem which was also making allthe pictures very blocky.

would ntl replace it with the new samsung box? because we are going to get the 2mb speed once it's in the area because we are going to network so it gets rids of me parents 56k.
currently we are using 750k in the digi box and due to move house on the 14th of feb, so the box maybe able to get swaped when ntl come in.