Some types of noises are normal in an LCD, LED, and/or Plasma Television. You will need to determine the type of noise to properly troubleshoot the issue.
Determine where the noise is coming from
First set the television's volume to "0".
Is the humming/buzzing noise coming from inside the TV?
Is the humming/buzzing noise overpowering the TV audio?
After increasing the TV volume to a setting between 30-50, listen to the humming/buzzing noise again.
If it is overpowering the televisions audio, the unit may require service.
If not, it is normal for the TV to produce a humming noise when the cooling fan is running and should not interfere with the audio of the TV.
Note: The cabinet may vibrate if the volume level is set too high.
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