07-31-2008, 03:31 AM
It could be an electrolytic capacitor going bad in a device somewhere. They ring like the dickens when they start to fail (not everyone can hear them and they look at you crazy when you complain ;-) ). Tube TVs (and even the DLP ones) do this as well depending on what is being displayed (lots of alternating white\black makes the ones at work go nuts and whine like mad). To find out if you have a problem with an electronic device, start unplugging things.
To rule out external vs. internal noise (despite having done a test by moving around the house), buy a set of cheap ear plugs and put them in. If the ringing gets louder or doesn't go away, it is your ears causing it. If it goes away completely, something is making the noise ;-)
To rule out external vs. internal noise (despite having done a test by moving around the house), buy a set of cheap ear plugs and put them in. If the ringing gets louder or doesn't go away, it is your ears causing it. If it goes away completely, something is making the noise ;-)