For Quite a while now I have been unable to recieve a number of channels on sky digital. It is so frustrating. The channels include bb1, 2 and 3 possibly others to. Also the itv channels and exetreme sports. There are others to. All i get is no signal is being recieved. Occasionally they will work for a couple of minutes. It has been suggested that the LNB is faulty. Tried switching it off and resetting it but this did not work. I am told that replacing the entire arm on my dish will cure the problem. The reason the whole arm must be replaced is that the LNB on the dish is too old and is not made anymore. Does this seem correct? If this is the case where will i be able to find one and will it be difficult to fit? Any help or advice would be greatly apprciated as it is so frustrating.