Why does my cd player create lots of huuuummmmmmm through my speakers?....It does this when i switch my pre amp onto the mains to charge.....Please keep replies very simple as i havent a clue about sciency stuff and certainly not whether its earthed or not etc....The hum is definately the cdp, because when it s off theres no hum at all...I use zanashs silver speaker cable and interconnects and mains leads ( a plug for you Z!), the mains leads covered in white placcy and the speaker cables in cotton.....any ideas or fixes...cheers banpe