How do I get rid of the buzzing noise in my speakers?

Speakers make buzzing noise whenever plugged into something plugged into the wall.?

• I can plug in my computer or my Ipod into my speakers with no problem. But when I plug either of those into the wall, the speakers start to produce a low buzz. I have pretty darn high class speakers (as in sound system) and I can plug instruments through things plugged into the wall with no buzzing (a guitar through a pedal or a plugged in keyboard). So, I would like to stop the buzzing and, for interest, also would like to know what causes the buzzing exactly. Thanks a lot!

• Answer:

  Mains electricity comes at 50Hz, (or 60Hz if you live in the USA). The alternating current at this frequency is audible. What you are experiencing is a 'hum loop', and it has nothing to do with the quality of your speakers, but the amplifier that is driving them. The amplifier's internal power supply is not filtering out the hum caused by the mains frequency and is actually amplifying it and passing it out through the speakers. Either the amplifier is crap, or its power supply has developed a fault, which is usually the capacitors which need replacing. Another cause could be a bad earth connection inside the amplifier.