Ferrites present a rising impedance to Radio Frequency
at or above a level (frequency usually in MHz) specified by the manufacturer of a particular ferrite. The ferrite then 'stores' this RF as an electromagnetic field around the ferrite itself.
Personally I have found that carefully selected ferrites do offer benefits in terms of sound quality.
My experience, for what little it's worth, is completely counter-intuitive, and derives from tinkering with clip-on ferrites of the type intended for computer power cables:
On analogue cabling, and on anything but the earth cable in power cabling, I found the effect universally deleterious. The effect is slight, only really noticable over extended listening sessions where it manifests subjectively as a loss of dynamics and realism. I'm at a loss to explain it.
Correspondingly, the one place I DO find them useful is on the aerial lead for my DAB tuner, where they help to reduce the effects of radiated EMI/RFI from other components without noticably attenuating the (already weak) signal!
Anyway, in this case these things are cheap enough for you to buy a couple and experiment - don't rely on anecdote: see for yourself!