Am I deaf?

I've got three CD outfits here on loan from my dealer. A Linn Ikemi, a Bel Canto DAC 1 running off a Pioneer 525 DVD player and a Classe CDP. They all sound almost EXACTLY the same. After hours of switching cables, power cords and anything else I could think of, I did form a slight preference. And that was for the Pioneer DVD running straight into my amp! This freaked me out so much that I subjected my wife to the same test. She also preferred the DVD player. What in the hell is going here? Associated Equipment: Classe CAP 100 integrated amp, Sennheiser HD600 headphones, Von Schewikert VR3 speakers, Cardas and Kimber cables.