Samsung UN40D5550RF E-Manual page 275

Issues
The picture is good but there is
no sound.
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Solutions and Explanations
•
Set the Speaker Select
•
If you are using an external device, check the device's audio output
option. (Ex. You may need to change your cable box's audio option to
HDMI if you have the box connected to your TV using an HDMI cable.)
•
If you are using an external device, check the device's audio output
option (Ex. You may need to change your cable box's audio option to
HDMI if you have the box connected to the TV using an HDMI cable.)
•
If you are using a DVI to HDMI cable, a separate audio cable is required.
•
If your TV has a headphone jack, make sure there is nothing plugged
into it.
•
Reboot the connected device by disconnecting, and then reconnecting
device's power cable.
English
option to TV Speaker in the Sound menu.
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