let me add that many poeple really do not understand AC, AF, RF, DC what these things really are and how to they relate if at all.
i could sit here and BS you with things like: hey what frequency is the DC for the USB buss that supplies the USB Power to the ODAC?
the idea for a usb cable that shielded and or has a ferrite bead....it to try to remove or keep out unwanted noise from entering the ODAC or circuitry in any way....either coupled or induced or coming from inside on the power or data lines.
sources for errant noise are
1. From inside the PC, induced usually via radiation.
2. RFI or EMI into the cable outside of the PC, from a stong magnetic source, electrical source ac , etc...
there is no way this type of interferance would normally affect the digital bits from the pc to the dac....it would have to really be somthing very powerful to negate the full amplitude of the digital bits....or interfere with the timing between bits.
if your envionment is fairly 'clean' you could use plain wires without shielding or grounding on one end....and all would be fine.
using a ferrite bead vs no-ferrite bead should not attenuate any of the actual content of those difital bits..there is no real way that a ferrite bead to remove these bits which if it could could then affect the downstream sound....
a ferrite bead is a passive device, it just is there....and when unwanted AC comes along...it help reduce or remove it from getting into the ODAC etc....so other wierd stuff wont happen...