W. Watson wrote:

In the last week, we've noticed that channel 3 has a very apparent noise
on it when it is on. If DirecTV is turned on, then the noise goes away.
We have two TVs on DirecTV and a third downstairs, which we can switch
over to DirecTV.
#1: Living room -- DirecTV
#2: Bedroom -- DirecTV
#3: Downstairs -- switchable to DirecTV

I've turned off my PC eqpt near #1, but no change. We've turned off a
few more household gadgets with no change.

This morning the noise is no longer on #2. No noise on #3. I don't
believe we examined #3 prior to a few minutes ago when I did check it.
We took #1 completely off--no antenna connection or power, and will
leave it that way for the rest of the day. It's the newest TV we have. A
Sharp 19" LCD.

I suspect the culprit will be the Sharp. Comments? The loss and gain of
the simultaneity of the noise on #1 and #2 to just #1 seems very odd.

Solved. When we were playing a DVD on the TV, I asked my wife to put the
subtitles on. She went to the TV menu, and somehow accidentally hit SAP.
That's what caused the noise. BTW, what's SAP?