You must try to understand that almost everything can introduce EM/RF noise. Every single device from the audio server, through every device my audio passes through on the internet and then my exchange to my router to my DAC can. Dozens and possibly hundreds of devices. But none of those sites think it necessary to use a magic cable or a magic switch. You really, really ought to attend a course on digital audio, or research it yourself
You must be kidding me, right??? No one believes it’s necessary to use cables or other devices to negate the negative effects of EM/RF noise that you finally concede can contribute to an audio chain via every source with an electricity source?? Seriously? Nordost, AQ, Isotek, PS Audio, Furman, Synergistic etc all have entire product lines to deal with EXACTLY this issue. No one calls it "magic" like you do - it’s all just reasonable isolation, shielding, grounding, and energy dissipation techniques that measurably work.
Why should I take a course on digital? This noise has NOTHING to do with the digital signal. Go do your own research.