LG UQ7570PUJ 50" 4K HDR Smart LED TV - Manual (Page 113)

The screen is fine, but it does not play any sound.
Try another channel.
If you use a set-top box, there will be no sound if you have set the volume of the set-top
box or your TV to 0 or enabled Mute. Set the volume to an appropriate level.
Sound Sound Out
Set the Sound Out to Optical Out Device + TV Speaker or Use TV Speaker , and then
check it once again. If you can hear the sound without any problem, check the
connection with external speakers such as sound bar and the settings of the external
speakers.
There is no sound coming from one of the speakers.
Sound Advanced Settings Balance
Adjust the balance as necessary with the Navigation button in Balance .
When you are connecting to the AV IN , check if the audio left/right (white/red) cables are
correctly connected. ( AV IN port is available in certain models only.)
The TV sound is not synchronized with the picture, or the sound sometimes breaks
up.
If this happens on only some of the channels, it may be caused by the broadcasting
company’s transmission signal. Please have your broadcasting services provider
(wired/cable) diagnose the problem.
If all channels are out of sync, go to Sound Advanced Settings Match
Screen and Sound and adjust the sync.
If you are using a set-top box, consult its supplier.
The volume changes when I change the channel.
The volume of different broadcasting stations’ transmission output may vary.
Sound Advanced Settings Automatic Volume Adjustment
Set Automatic Volume Adjustment to On .
If you are using a set-top box, consult its supplier.
The volume keeps changing.
Sound Advanced Settings Automatic Volume Adjustment
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