I've always admired James Randi, but in this case Fremer has a valid point- as a condition of the test, Randi says that Fremer winning the challenge will be evidence of paranormal powers! Fremer is a bit of a flake but doesn't think hearing cable differences is paranormal at all; he thinks there are audible differences. Randi is a bit wide of the mark here, IMO. Certainly there must be a chance that some real, physical property, even one we haven't yet learned to measure, could be at work as opposed to the occult?
I'm cable agnostic. While I can't honestly say I've heard differences between well designed cables, I do "hedge my bets" to a degree. I wouldn't spend $7,000 on a set of cables if I was a millionaire but I will and have spend $200 on a digital cable or IC. And I have little sympathy for the cuckoos that buy Shatki Stones, but I'm willing to admit that my ignorance of something or inability to hear a difference doesn't automatically equate to that difference being imaginary. Randi is correct that rigorous scientific testing will determine if one is able to tell the two apart, but any claim of being able to tell why or how the difference was detected would seem to be idle speculation on his part.
Of course, The Foundation exists to debunk supernatural claims and expose hucksters and con men. This seems a bit out of his normal area of concern but it's his Foundation!