Go to the device manager and expand the audio, video and game controllers, uninstall the audio device (not the realtek hd audio device), and then reinstall it again.
Hi-
I brought my tv from Africa. Looks like something happened along the way. The image is perfect but audio comes and goes. Sometimes when you hit the back of the tv it's ok. But it's hit or miss. This happens with the XBox and cable. I replaced the HDMI cables to no avail. It's an LG 42LN5100. Help!

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