Replaced CDP w/ Transport; Now, Soundstage Changes Dramatically w/each CD. Why?

Here's something I've never encountered. I've borrowed  a Heed DT Transport and am loving the increased resolution, compared to my Jolida JD100 cdp BUT, now the sound-stage expands and contracts, depending upon whichever CD is being played.The effect is very evident-- not subtle. This is really weird. 

System: Heed Transport -> Aqua La Voce II DAC -> Wells Majestic Integrated -> Silverline SR17.5 Monitors.
 
I don't even know where to begin. . . any suggestions? ? ? 

BTW, replacing the Blue Jeans BNC cable with an Empirical Audio BNC cable didn't change anything.