Loud white noise sound when i switch my LCD tv on.

Samsung LCD TV with no video and high pitched sound - Digital TV ...

www.tomsguide.com/forum/54120-4-samsung-video-high-pitched-sound

Jan 7, 2010 - 26 posts - ‎15 authors
Hi, I have a Samsung LN40A550 LCD TV which I have had for just over a year. ... I was watching TV yesterday and all of a sudden the picture went all. ... started makinga very high pitched buzzing sound with no picuture coming on. We did have a bunch of green vertical lines, but now just a black screen.

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Samsung LCD Loud Noise and Green Vertical lines at Start up ...

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I would suggest you take it to a service center , sounds like an internal problem .

If you have warranty left- replace it.

The main power supply regulator section circuit fault. Either it will be a separate board, or the part of main board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
It will be best to replace the power supply regulator board as card basis rather than making "Surgery" to it; which usually will make loss for both money and time. Even though you can make it right, it will cost around an amount equal to the cost of a new board; including the cost of (spare parts + service charge) More to say, most of the spare parts to it will be difficult to get from open electronic spare part market. This is true to most of the flat panel TV power supply boards; irrespective of its brand and screen size.

A common cause are failure of decopling capacitors in the audio section, and or the circuit board power distribution that feeds the audio board. Most of the capacitors are surface mount components. The standard fix is to start by changing the circuit boards that have the defective parts.

If the set is under warranty, call for warranty service. Out of warranty service is expensive for these TV sets.

Jerry G.

crackling in the speakers of 42"flat screen tv

lcd tv's have a compact swtich,it will be little difficult to find one,try to search in computer hardware shops u will get many,if ur recipt is lost no problem go to the shop and ask a duplicate recipt or show ur transction or ur lcd's seal .

no

Find out if Australia uses a different standard of HD programming than Guernsey or not since it's not picking up any channels at all with an attenna. Does the skybox use only scart connections and that's how your small lcd is connected to it?

Perhaps your remote is set to video recorder?  Try that first, and if no response, try calling up a menu on your TV and look for the Picture Settings.
Good Luck.