right then, here are the problems:

watch one channel, all fine
recording channels, fine
but recording channels and then trying to watch another reveals "no satalittle signal being recived
and trying to record something while watching another channel ends up with "recording failed"

checked the signals and there doens't seem to be a second signal coming in, so swapped the wire sin the back over and still the same problem

dodgey wire?
dodgey lnb?
will i need a sky bod to come and sort it out?