Earthing

As soon as you start sending a signal from one device to another, it becomes susceptible to all kinds of interference that can show up on your track as unwanted buzz, fizz and hiss. The most common sort is earth hum. In a perfect setup, all your audio equipment would be grounded at a single, very effective earth. That way there would be no current flowing in conductors and cable shields, and consequently no current introduced into circuits and signals. Your home probably has reasonable earthing, but the actual earth points can be numerous, shared between houses and sometimes a good distance away. Installation may not be up