Plazma TV buzzing noise

Question

I have recently purchased a PS50P91 Samsung 50" 1080p HD TV. The TV seems to makes a buzzing noise which comes from the back of the TV, however it is loud enough to hear from 3m away when watching low volume broadcasts like the news.
I have done some research and contacted Samsung but I'm unable to get a firm answer. I have been told things like room acoustics, TV distance from the wall and various other reasons can amplify the buzzing noise. I understand that plasmas do make a low level buzzing noise when on but it shouldn't be loud enough to hear over the TV.
Any suggestions?