Sorry, Rotarius. I would agree with you except that many of us have heard a distinct improvement in the sound of some equipment using different coupling or isolation devices. I do agree that any one of these may not work in any given situation. I'm an EE and your arguement sounds much the same as what I hear from other EE's when I try to explain why I choose to spend money on cables. I choose to use some hi-end audio cables and some isolation or coupling devices based on what I hear from the use of such things. If they don't produce a change that I like, I don't use them. If I do like the change I then have to decide if the change is worth the price of the item. And that is a whole 'nother debate.