Hi. I just bought a new Sony Bravia 32 inch M4000. Thing looks great. But there is a low (but noticeable) hiss coming from the speakers. It only occurs when the speakers are on, i.e. if I go to 0 on the speakers the hiss goes away. But it comes back when I go to 1 or when I am watching tv. It's not the loudest thing ever but I have really good hearing so I definitely notice it. Is there anything in the sound settings I can do to fix this? Could it be a bad tv? Thanks!