Samsung PX5ISDBA E-Manual page 177

Issues
The picture is good but there is
no sound.
◀
Solutions and Explanations
•
Set the Speaker Select
•
If you are using an external device, make sure the audio cables are
connected to the correct audio input jacks on the TV.
•
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 when you have a HDMI connected to your TV).
•
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 reconnecting the device's power cable.
English
option to TV Speaker in the Sound menu.
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