Ferrite beads/clamps as a tweak?


I've been reading that ferrite clamps can reduce RFI/noise on just about any cable - power cord, video RF cable, IC, etc.
Can they also hurt the sound? Why wouldn't you want these things on every IC, power cord, video cable, and so on - even household appliance cords like the fridge etc? Do they reduce RFI leaving the appliance or just entering the device?

It seems like putting these things all over the house would do a great deal to reduce noise. I don't have any specific interference problem except with cable and FM reception. Seems like an obvious idea for cheap system tweak.
gdoodle
I used ferrite chokes on my ICs and pcs for years, and although I can say that I didn't preceive the difference either pro nor con, after reading a couple post concerning them I then pulled all that I had on and I find the presentation of the music I enjoy to be natural in the way it was intended. In looking back I may have effetced the micro dynamics a bit but then again it never did have any noticable harmful effect either.
on AC cords no perceived problems here...
on unbalanced interconnects; HF attenuation was an issue using Audioquest RF Stoppers
Over the years, I have used a varity of ferrite blockers/stoppers on power cords as well as interconnects. In my applications, they absolutely provided positive changes in that the noise floor was reduced. In using them however I had to "tune" the blocker/stopper to the best location on the cord/interconnect - to close to the source or to far away from the source resulted in too much or bloated bass or the sound suffered from compression. Once in the right spot on the cord/interconnect, they proved to be a most beneficial and economical tweak.