Buzzing that occurs in a plasma TV is more noticeable in a room that is very quiet. The noise comes from electrical charges that power the pixels to create images on the screen. The buzzing sound may also come from electromagnetic interference from other items. Your TV's picture settings may cause the noise to occur too. Although the sound will always be there, you can drastically reduce hearing plasma TV buzz.
Remove sources of electromagnetic fields away from the TV. Kitchen appliances, light dimmers, fluorescent lights, mobile telephones, radios, power tools and microwave ovens are a few examples of products that should be distanced from the TV and connected to another outlet.
Set the volume at the normal setting that you prefer and then stand back 10 to 15 feet away from the TV.
Perform a sound test. Most plasma TV models have a Self Diagnostic option accessible from the Menusetting. The steps may vary from your model, but should be similar. Press "Menu" on the remote control and then press "Support." Press "Self-Diagnostic" and then press "Sound Test." Your TV's sound is not defective if you do not hear any buzzing. Refer to your owner's manual on how to perform a sound test for your specific plasma TV model.
Rearrange any cables that you find lying on the back cover of the TV. If the back cover is metal, cables that touch it may cause the TV to produce buzzing sounds.
Turn the TV off, remove all cable connections attached to it and unplug the power cord from the AC wall outlet.
Wait 30 seconds and then replug the TV.
Turn the TV on and then increase the volume to a sound level of 15 to 20.
Stand 10 to 15 feet from the TV and then repeat Step 2 to perform another sound test. If you hear buzzing, reduce your picture settings for "brightness," "contrast," and "back-light" or "cell light" settings by 50 percent. Repeat Steps 1 and 2 to perform the sound test. Otherwise, if you do not hear buzzing after you performed the sound test for the second time, the issue is not with your TV. Replace over-sized cables and avoid connecting devices to the TV that cause it to buzz.
Plug the TV into a wall outlet instead of a power strip to lessen the chance of plasma TV buzzing.
Changes in a room's temperature, such as increased humidity may contribute to loud buzzing. Keep the vent on back of the TV free of obstructions so that fresh air can flow around it.
High altitudes will cause buzzing in some plasma TV models. Your owner's manual should contain altitude range recommendations.