When i plug my new tv into the sky box via a scart, the tv picture is distorted and a major buzzing noise is coming from the tv. sky have checked and said the box is fine. when u connect to another tv it is fine.

Have you tried another scart lead? Also tried all of the tv scart sockets? Don't try and cure this by using an expensive upmarket scart lead, you'll just be wasting your money. The cheapest leads work just as well when the function correctly.

You could also try reversing your current lead by swapping the tv end to the Sky box and vice-versa, as there are many leads which cause feedback issues, and also a lot of "cut" leads (designed to prevent feedback looping) which must be fitted the correct way around. A "cut" lead is one where the wire to pin 19 at the tv end and to pin 20 at the video/Sky box end has been cut.

Note that scart leads MUST be fitted with the tv and Sky box switched off to avoid damage. Most people (including professional installers) regularly ignore this precaution though.

If all else fails then take the tv back and exchange it under the Sale of Goods Act; it's certainly not uncommon for new tv's to have faulty scart sockets.

If I've solved your problem then please take a moment to rate my answer. If not, then please report back with the make and model of TV and I'll try a more specific answer.