hello friend, i'm matt and a sky engineer.. to be honest it could be a few things really.. first off start with a software download, remove card, switch off box at mains, press and hold 'back up' on front of your box and switch box back on, after 15 seconds or so you'll have four lights on front of box and message on screen.. leave for 10 to 15min, put card back in and switch back on..
if that didn't work, i could be your quad LNB, shpuldn't be tho as you try'd your other box..
its prob the tuner or power pack inside your box, they are about £18 each to buy from specialist shops, maplins etc..
and you can do it yourself with a soldering iron and a little time.. hope this helps, matt.. abercraf@hotmail.co.uk
matt, June 2007