This problem occurs due to IR noise received by the IR receiver on the Cable/Satellite/Set-Top Box which originates from the screen of the LCD TV. This IR noise drowns out IR signals from the remote of the Cable/Satellite/Set-Top Box due to which the IR receiver cannot properly decipher the IR signal it is getting from the remote.
All LCD TVs emit a certain degree of IR radiation but only some external devices with certain types of IR receivers are affected. The amount of IR radiation being emitted is more for large screen TVs.
Elevated levels of IR radiation are emitted under the following conditions:
- When the LCD TV back light warms up when the TV is switched on
- When Image Enhancement features such as “Dynamic Contrast”, “Active Control” or any similar features which dynamically adjust the intensity of the LCD TV’s back light are active
Ambient conditions which make the problem worse:
- Reflective paint, mirrors or reflective surfaces around the LCD TV will intensify the amount of IR radiation being picked up by the IR sensor on the Cable/Satellite/Set-Top Box
- Positioning of the Cable/Satellite/Set-Top Box with respect to direct and reflected IR radiation from the LCD TV
Solution/s:
- Make sure the batteries in your Cable/Satellite/Set-Top Box remote are not weak. Try replacing the batteries.
- Position the Cable/Satellite/Set-Top Box in such a way that the amount of IR radiation being picked up by the IR sensor is minimized due to ambient factors such as reflective paint, mirrors or other reflective surfaces.
- Turn off Image Enhancement features such as “Dynamic Contrast”, “Active Control” or any similar features which dynamically adjust the intensity of the LCD TV’s back light.
Supplementary (crude) Solution: (If the solutions above do not suffice)
Cover the front panel of the Cable/Satellite/Set-Top Box with opaque tape in such a way that only a small window is left open for the IR receiver to accept incoming IR signals from its remote.
Note:
- Solution 1 is applicable to all LCD TVs
- Solution 2 is applicable to TVs with features such as “Dynamic Contrast”, “Active Control” or any similar features which dynamically adjust the intensity of the LCD TV’s back light