AV Sync Setup
Start by going to:Sound AV Sync Adjustment
Adjust the synchronization of the sound from the speaker with the TV.
The closer to the Minus Sign (-), the longer the audio output time. The closer to the plus sign (+), the faster the audio output speed compared to the default.
If you select the Bypass, Outputs the broadcast signals or the sound from external devices without any audio delay. The audio may be output before the video because of the time the TV takes to process the video input.
Turn the TV OFF and then unplug it
Now hold down the POWER BUTTON for 15 seconds ( the button that is in the middle of the TV just underneath)
Now plug it back in and TURN IT ON and check to see if it is still out of sync.
Still Experiencing Issues
If the prior steps have not mitigated your issues, we recommend contacting one of out LG Customer Support Representatives.