Should my power supply buzz/hiss?

[magick]

Got a Sony m2 and the power supply kept buzzing so took the power supply back and was given a supply from a z1 which worked fine. My earphones broke and I've been given a new phone but had to give the old one back along with the z1 power supply. On the new m2 the power supply is buzzing again. Is this normal or should I am for a new power supply?

 

[Something Else]

The power supply is basically a transformer and will buzz slightly but you shouldn't hear it really on a modern phone charger.

Id be wary and perhaps purchase a decent one from belkin or something.

 

[insane200]

My Nexus one buzzes apparently, i cant hear it but the mrs always moans about it.

 

[Beerbaron]

My official Samsung charger buzzes. I have an iPhone USB cable plugged into in though