Gulio at Matrox offered great over the phone tech support. He immediately filled out an RMA to replace my faulty MXO. No redundant troubleshooting necessary, he said, I trust you went through the steps I outlined in my forum post and that’s good enough for me.
This is customer service the way it’s supposed to be. Better than it’s supposed to be, actually. I’ll update as soon as I receive the replacement MXO, sometime next week I suspect.
In related news, the OptShiftK team came over tonight doing a test calibration of my Dell 2407WFP with both the Spyder 2 Pro and Spyder 3 Pro. Look to the new brain trust blog http://www.optshiftk.wordpress.com for full calibration details (coming soon).