You use the Red/Green pair on 2 pair I/O cable only. They should've used the WH/BL, BL pair for the primary then moved to the orange if the blue was bad. Cat 5 is twisted at a different twists per inch on each pair. For instance a 25 pair cable can be twisted at 60 t.p.i. But look at a cat5 cable and the blue pair is twisted much tighter than the brown pair. twisting prevents cross talk, the only difference between cat5 and other cable is that each pair is twisted at a different rate. I think I know the guy that did that job. I FIRED HIM!!! Hope this helps , later, Red