I think these machines only have two tuners - so you can only tune into two programmes at the same time - on our Sky Box for instance we can record two programmes at once but it will not let us watch a third programme - because the two tuners are busy. If we record two progs at once we either have to watch one of them or switch the TV to another input source to watch something else.
It may be a case of three into two doesn't go...
Good luck...
Peccavi, December 2009