Timrhu, I strangely had a similar experience when I purchased a used pair of speakers, a $6500 pair no less. But in my case, it was with a set of IC's. My wife called me at a friend's house to say that she thought the speakers sounded lousy (mids/highs recessed and muddy), and I agreed, having listened to them for an hour or so earlier in the day. We did not want to keep the speakers. The seller agreed to take them back (I'd picked them up only hours earlier), until I tried something out just for grins.
We had volunteered for a beta testing run on IC's, whereby one set would be sheathed with two layers of carbon, and another identical set would be left stock. We had two identical sets of IC's (same model, same manufacturer). I was at the time running the set with the carbon sheathing on them. When I switched over to the 'untreated' pair of IC's, all of the frequencies fell into balance. The muddiness was gone, and we kept the speakers. I still think this is one of the reasons that Audience AU24's (and Speltz anti-cables) are so popular, because all of that extra layering (which the Audience and Speltz DON'T have) can potentially veil the sound. This is why I am convinced that cables can make such a big difference, because I've experienced it first hand.
Does this mean I put stock into a Stereophile review? Heck no!