Steve: If both of the additional magic eyes are known to be working, and that they were definitely tried in the Sky boxes RF2 socket and not accidentally in RF1, then the fault must be with the box, because even although your cousin may well have seen 9 volts being indicated on his meter, the reading could well have dropped to zero as soon the eye was connected into the socket, as its not exactly unknown for a voltage regulator to develop a problem whereby it fails on load.
You should get your cousin to prise open one of the magic eyes and measure the voltage whilst its plugged into the RF2.
during the last week my sky program on 505 CNBC has been either off or badly distorted. All other channels work perfectly although occasionally channel502 Bloomberg has also been unstable.Last night at 7PM it did work for some time perfectly but no signal again this morning. Ellis Philip Inchmarlo AB31 4AF