This Supra HumBuster is a Swedish box designed to remove the noise and hum from your computer audio visual components. In reality it’s something called a ground separator (or earth separator in English?) which deals with the loop currents which cause those annoying humming sounds in audio systems. Practical and useful. £99.99.
Hum or noise? Sparks or wandering picture phenomena? Most likely the culprit is different grounding potentials in the items connected to each other. That creates earth loop currents, which interfere both sound and picture. Not only causing mains network hum but also causing other noise from light dimmers, electric motors, fridges, etc. Should you get your TV signal from a Cable TV Network you are at an extraordinary great risk.