i recently purchased a pair of MSP5A's. now i was so excited to finally have a pair of decent monitors, as before i was using a very consumer-oriented Klipsch Promedia 2.1. However, it has only been the second day and I don't even want to listen to them anymore. When I first powered them on what struck the most was the incredible clarity especially at the high end. I could hear the hihat lines in many tracks with stunning precision, and several hidden details in songs came out. However, I noticed that only after 5 minutes, I was not very eager to continue listening. I wanted to take a break. I kept telling myself that it was just a coincidnece, but after several tries, i always felt the same thing. I just couldn't listen to them for more than 10 minutes without feeling... annoyed, tired... also strangely I found it very difficult to "zone out" and focus on the music like I usually do. This morning, with a fresh ear, I noticed the more i turned down the right speaker, the better it sounded. In fact, it seems that I prefer everything that comes out of the left speaker. Coincidentally, my right ear seems to be far more aggravated than the left. I then did a couple of tests of playing a mono track and then soloing either speaker. I found that there was a subtle but noticeable difference. One speaker sounded more 'tame" and precise, the other sounded a bit louder and rather "noisy" - it had little focus and I would have difficulty getting any kind of sonic image out of it. I am somewhat positive that they are not sounding the same. Also when I opened both speakers, I noticed that one speaker was left in the ON switch and the volume knob had been turned up halfway, whereas the other one was left in the OFF switch and the volume knob was at zero. Which leads to believe that one of them was either refurbished or not at the very least, not exactly brand new. Could this be a plausible explanation for the ear fatigue? Or I am just imagining things when the real problem lies elsewhere?