There has been some fantastic feedback on this thread! I have learned quite alot, and it is obvious that there are some extremely bright and talented people visiting this website.
In spite of my initial problems with my D6000s, I am now a Meridianite. I will do whatever it takes to get these speakers working properly, or at least determine exactly why they will not.
One of the original D6000 speakers is on its way to Meridian in Atlanta. I took the upgrades out because I could not see spending another $5000 when the upgraded speakers had the exact same problem as the D6000s without the upgrade.
In my spekaing with Jason at Meridian Atlanta, I am confident that he will be able to determine what the issue is---it it indeed that I am overdriving them in my room set-up, or is there somehting else that can be rectified (I really hope it is the latter). Jason is also looking at the DSP6000 center issue (the woofers have a loud crackle). I do not know if the center has the same volume overheating issue because I have never been able to play it due to the woofer issue (I just purchased the center from World-Attorney through this website).
The M&K speakers I am currently using are the full s150 system with a Denon 5803 (they sound fantastic and I have never had any issue whatsoever playing them at the same volume I have tried on the Meridian gear).
So far, no one has tried to calibrate the D6000's nor even suggessted it, except on this thread.
I am using the original cables that came with the eBay and Hitchhiker purchases.