Samsung LED 4500 Series E-Manual page 189

There is something wrong
with the TV.
The TV is making a
humming noise.
Image Retention (Burn
In) Issue
Your TV utilizes high-speed switching circuits and high levels of electrical
current, and depending on the brightness level being used may seem slightly
noisier than a conventional TV.
Your TV has undergone strict quality control procedures that meet our
demanding performance and reliability requirements.
Some noise coming from the TV is considered normal and is not an acceptable
cause for an exchange or refund.
This issue affects PDP TVs only. Watching TV for an extended period of time or
using the 4:3 screen ratio only may result in burn-ins.
PDP TVs are equipped with Pixel Shift screen burn reduction technology. Pixel
Shift technology reduces screen burn-ins in PDP TVs.
It does this by moving the picture slightly vertically or horizontally.
Screen Burn Protection
Use
to prevent screen burn-ins.
Try this!
(Screen Menu > System Screen Burn Protection)
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