BUSH DTR no longer series links =[?

My year old Bush DTR works fine, other than it no longer offers a series link function? When selecting a program to record, it puts it into the list without offering the menu where you can select to record it as a single or to series link it...

I have formatted the box and it still only offers single recording, so now I am stuck with what to try next...

Help please?

Evedy
December 2010