Does anyone else hear a high pitched whine emitting from their WRT54G routers? Does it happen occasionally, all the time, or not at all? I'm sitting next to it and can definitely hear it. It's like a faint dog whistle. I don't know if I should try to exchange the unit.... might be too late since I just updated with the HyperWRT firmware; or just snuff out the noise by putting it behind my cabinet. Or hit it or what.