I agree with Chris, lately I've been playing about with a couple of 24/192 USB to spdif converters, using the stock Musiland USD to provide spdif to the Caiman the sound was quite sharp , swapping over from the Musiland to the Hiface things was more natural, I've had same differences using various CD based transports.
I found using co-axial input the quality of the transport had quite an influence on the sound no matter which of my dacs I use, even the ES9018 Sabre based dac with its Time Domain Jitter Eliminator