No SKY programs linking through to TV?

Hi,

We were watching a SKY program and the screen went black and white and then went blank. It then reverted to normal TV viewing. We tried by using the AV button to get back to SKY but it wouldn't show anything. Tried turning off and on the SKY box, replaced the SCART lead, took out the SKY card, still nothing.

It can't be the TV as I can see all the normal digital stations fine, but when we try and switch to SKY, the screen is blank for a few seconds and then reverts to normal TV. The SKY set looks fine as it's ON and the green light is on.

We've had this SKY box for 2 years with no previous problems.

Thanks for your help