This just happened to me with a recently-rebuilt 3910 Denon where 32-bit AKM DACs, a digital input and Class A tube output stage are yielding the most detailed, involving, transparent and musical presentation I have ever heard out of my system.It sounds to me like you may have come to the same conclusion as I did. Specifically, that the APL Denon 3910 with digital input sounds better with an outboard transport than it does with the Denon's own transport.
Fplanner2000 (System | Threads | Answers)
I'm using mine with a relatively inexpensive Music Hall CD25.2 modded as a transport by Parts Connexion. To my ears, the sound is fuller, richer and more meaty with the Music Hall transport than with the Denon alone.

