I would have to agree with Guido on the possible challenges above. No matter what tweaks I made, I always preferred the timbre, grain free sound, depth of soundstage, etc. playing RB CD's in the K-03 Transport vs music files played using the K-03 USB input.
The next move was to replace the HD in my 2010 Mac Mini with an Agility 3 SSD. In addition, I added the Bel Canto Reflink to the mix via BNC/SPDIF (Transparent Reference Digital Cable) to K-03 Coaxial input.
I kept the Audioquest Carbon USB Cable to direct USB Input to perform an A/B comparison and could now evaluate all three options. The differences for me now between spinning disks and listening to the like Redbook CD file(s) are indiscernible, I can hear no difference. Seems the SSD and USB Converter reduced the noise inherent in computers while reducing jitter.
Mark