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Sound like an electric razor

V

vchimpanzee

Credits and other similarly displayed information used to cause this noise.

But now? On digital channels? How can that be?

I had to switch TVs last week and that's when it started.
 
It is your TV. The problem occurs with many CRT TV's. It does not matter how the signal gets in (cable, OTA) or the method (digital, analog). When a lot of white is in the image...that sound can bleed over to the speakers. If you mute the sound, it will go away (along with the other sounds). I don't know what exactly causes it, but I think it involves the electron gun used to display the images. This is a very common problem.

I have had an LCD for the past couple of years...and I have never heard that sound.
 
Yep, an LCD will do it, but needs an analog over-the-air signal with a high contrast level ( typically a dark screen with white letters ).
It's caused by the "overshoot" from full blanking of the video signal putting byproducts into the audio bandwidth area.
Turning down the contrast will help some. Most of the time people tend to turn the contrast up way too high for "snap" in the picture, and this
makes the buzzing worse. Even correctly adjusted sets will make this noise sometime if the source video has too much contrast.
I've never heard this sound on a truly digital signal, so perhaps if you haven't heard the sound on your LCD, you might have digital cable.

I thought it was just the CRT technology, too, but I did witness this effect in March with a new LCD TV, watching analog over-the-air signals.
 
vchimpanzee said:
Credits and other similarly displayed information used to cause this noise.

But now? On digital channels? How can that be?

I had to switch TVs last week and that's when it started.
Click to expand...

This is known as Incidental Carrier Phase Modulation (ICPM), essentially the lumanence signal, from a saturated white picture, is getting in and "phase modulating" your aural carrier. This can happen with anything that RF modulates. Analog television transmitters, the channel 3 output of your converter, your VCR output, the cable system, and so on.

Look closely at your install, something is doing it, not the broadcaster.
 
Ron said:
vchimpanzee said:
Credits and other similarly displayed information used to cause this noise.

But now? On digital channels? How can that be?

I had to switch TVs last week and that's when it started.
Click to expand...

This is known as Incidental Carrier Phase Modulation (ICPM), essentially the lumanence signal, from a saturated white picture, is getting in and "phase modulating" your aural carrier. This can happen with anything that RF modulates. Analog television transmitters, the channel 3 output of your converter, your VCR output, the cable system, and so on.

Look closely at your install, something is doing it, not the broadcaster.
Click to expand...
I figured that. Actually, I've replaced the TV. More about that on another topic.
 
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