ok, ive just come to wire up the ir receiver and just realised my cable only has 4 wires and in the reciever it has 5 junctions, my question is which one could i miss out , i know its a daft idea but it is my only option as the cable is sunk into the walls, please help

See http://beotech.beoworld.org/ir_eye_wiring.htm

Might give you some clues. You are advised to use the oiginal wire supplied and keep to the original length. Something to do with the impedance I believe.