Cable feeds can be really problematic. I had noise issues what went away when the cable feed is disconnected. The cable feed is to the television system, which, back then, did not have any direct connection to the stereo system. But, both systems were no the same branch of power feed, so that is how the noise got to the stereo. Even an isolation transformer did not do the trick. The cable company eventually solved the problem. That is a good thing because now my music system IS directly connected to the cable feed. I need an internet connection for the music server. To me, stuff like an isolation transformer is more like an essential component (something designed and used to solve a specific problem), and is not so much a tweak. I suppose something like power conditioning is in the grey area between component and tweak in the sense that there are those that find power conditioning to be overkill. I recently added an Isotek Titan and Isoteck Evo Sigma conditioners to my system. They changed the sound to a meaningful extent and I like the overall result, but, like anything else, there are some trade-off involved. More clarity, more precise imaging, a plus; a slightly drier sound and more obvious recording flaws a minus.