Basic Info: I2S is a standard for internal data transfer of 2 (or 3, depending on implementation) clocks and a data line. These should be in sync (and not spread across different length wires such as CAT5 standard - which is NOT meant for this). A simple CAT3 will match the requirements of I2S as long as it's under 12" in length - anything longer will be out of spec and outside of the designed operating range (and into "I am audiophile and I say something sounds good without proof, idea, concept or anything else" area - mainly what I call audio-bull).
I do experiment and evaluate different cables, both digital and analog, though I apply physics and "general" principles into my evaluations. When something makes no sense - such as "magic custom cable for some digital line", I challenge it, make one of my own, buy the "trial" one and look into technology as well as my own testing to find a conclusion.
Anyway, having used the NorthStar m192 DAC (which I really do like, and plan to buy again), I have personally concluded (which I pursue and encourage others to try, experiment and play with) that the internal S/PDIF to I2S conversion isn't as well implemented as possible (my personal digital - whichever I may choose, mostly straight southbridge to I2S through ESI Juli@), is not as good as possible.
Simple idea - I2S is the best way to transfer digital audio; as long as you can transfer it in this format. Get all the data, send all the data and make sure you send all data and clock lines to make sure everything get through. S/PDIF is a 20+ year old standard that is simply out-dated with what modern equipment can support. Trash the old, go forward with the new and REALLY use audio.
