Samsung UE50ES6300U E-Manual page 707

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.
ΠIf you are using a DVI to HDMI cable,
a separate audio cable is required.
ΠIf your TV has a headphone jack,
make sure there is nothing plugged
into it.
ΠReboot the connected device by