It would seem the amp is fussy about speaker pairings. However there is no guarantee the Nad you suggest would be better (though the chances are it will!). I would suggest that throwing cash at the problem is not the solution here, you need to demo any choices. That suggests finding a dealer that will allow home demonstration.We first partnered the SA-XR10 with a speaker package, and frankly, we were underwhelmed by the brash, hard sound; sitting through even a single DVD was a trial. That's funny because the Polk kit won us over when it was teamed up with our Pioneer VSX-27TX receiver. We took the hint, swapped out the Polks, hooked up our Energy Take 5.2 system, and bingo--the gritty sound disappeared. Even when we tried a less than stellar-sounding DVD such as Pulp Fiction, the XR10's sonics were quite acceptable. The lesson that we learned: The XR10 is picky about speakers, and the Energy's laid-back demeanor was a better fit. We'd guess that Paradigm, Mirage, and Infinity speakers would also work.