Nick - Did you reference the Wavelength link I provided? Here's some info from that link:
I believe your Digitech is acting as an upsampling soundcard. Regardless of upsampling it is processign the data from the HD and sending it on to the DAC via S/PDIF (unidirectional). My guess is that the 'compromise' lies in the Digitech.
Marco
Basically the DAC has a single digital USB input. USB unlike SPDIF is bidirectional and therefore has error correction and buffering on both sides. This happens automatically so the data on the disk is identical to what is going out all the time. Also since this interface is asynchronous the clocking problems associated with SPDIF go away. What happens is... On power up of the computer the 2 devices negotiate services. In this case the Cosecant tells the computer it can do 16 bit audio at 32K, 44.1K and 48K. Since the USB receiver only has to handle these 3 frequencies, the clocking to the separate DAC IC has almost no jitter. SPDIF actually has to be synched to the exact frequency of the transport (i.e. if the transport is working at say 44.0896K instead of 44.1K the dac has to sync to that frequency). Therefore the jitter problems of SPDIF almost go away using USB. So using USB we have a zero error protocol to link the computer to the DAC and very low jitter what else..... The Cosecant is platform independent also OS independent. Any computer that has USB output will be able to hook up to the Cosecant without software drivers. Just select the Cosecant for Audio Output in your system preferences or control panel and your done.
I believe your Digitech is acting as an upsampling soundcard. Regardless of upsampling it is processign the data from the HD and sending it on to the DAC via S/PDIF (unidirectional). My guess is that the 'compromise' lies in the Digitech.
Marco