Default Low white noise in headphones (charger not connected)

Hi,

I just bought a Nexus 10 are now having a small problem with a low white noise when I use headphones/headset. When no sound is playing there are no noise, but when a sound is played and thus activating the audio output a low white noise can be heard in the background and is present until the output is closed. The charger is not connected when this happens, and I have tried with 3 different headsets.

Does anyone have an idea how I can fix this or do I need to contact Google/Samsung for a replacement?