> I've since obtain a Furutech Formula 2 usb cable to test the input again. I've been using it for a few weeks now and have yet to hear a skip. It also seems a tad warmer, but slightly more detailed than optical.
Oh. Wow. I think you've just convinced me that all cables are a placebo effect, because...
This is the very definition of placebo effect. As a computer engineer, I don't know how to stress enough that there is literally no difference from one USB cable to another, unless one is broken entirely (loose wire). Again, it is impossible for the data from USB cable to differ from another, other than one being flat out broken.
Your sound is sent from the computer across USB as digital information - 1's and 0's basically. All working USB cables achieve this with 100% accurate reproduction. This 100% is not an exaggeration. This is not analog, there is no possibility for voltage/conductivity effects, etc. to make a difference. Repeat after me: 100% accurate reproduction.
The conversion from 100% accurate digital to the analog that eventually makes it to the drivers is done by the DAC (which is inside the box and has nothing to do with the cable), which an important part and certainly can effect the sound.