Sure, but I believe the more important question should be, what might cause the perception of an audible difference, physiologically.Right...
Is there an audible difference under controlled conditions. If that can't demonstrated, there's no problem to be solved.
For example, it could be possible that this ability/anomaly only occurs in a very small percentage of people or only under very specific circumstances.
Thus by simply performing a test on random people under conditions that may not be conducive or optimal for this phenomenon to occur, the results would obviously be inconclusive.
That's what I mean by first attempting to explain what it even is that people are experiencing while only performing tests to prove or refute it, after the fact.