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  NS-27 serves as the model number for a 27-inch LCD television set bearing the brand name Insignia. The Insignia product line is offered exclusively at Best Buy stores.LCD televisions are flat panel sets that use a liquid crystal display to present the images. Like any type of electronic device, LCD televisions are not without problems.
  
  

Horizontal Dotted Line

• A horizontal dotted line can be produced by interference from other devices. The list of devices that might cause that type of interference includes hair dryers and neon lights. Moving the television away from such devices can solve the problem. Switching the device off or moving it away from the set can also be a viable solution.
  
  

Image Burn

• Using the Insignia NS-27 LCD television with any device -- such as a computer game system -- that projects a constant image is not recommended. Leaving a steady image displayed on a section of the screen can cause screen burn. Screen burn will be seen on the set as a faint image that persists. Screen burn is a problem that is not covered by the warranty of the unit.
  
  

Other Picture Problems

• If there is no picture on the screen, it can be caused by having the video mode set incorrectly. Having the television set to a channel that is not broadcasting, can also cause this problem. A snowy picture can be the result of loose cables. In addition, glare from a light source can cause reflections that will have a negative effect on the picture quality.
  
  

Sound Problems

• Selecting the wrong audio mode can produce less than optimal sound quality on the Insignia NS-27 television. When using an auxiliary device, such as a DVD player, with the unit loose or with improperly connected cables can cause poor sound or no sound at all. A crackling sound in the television (not through the speakers) is caused by expansion and contraction of the unit from heating and cooling. That is a normal part of the operation of the television.