Using an Optical (Digital) Cable ConnectionAvailable devices: Digital Audio System, Amplifier, DVD home theaterDIGITAL AUDIO OUT (OPTICAL}" When a digital audio system is connected to the DIGITAL AUDIO OUT (OPTICAL} jack, decrease the volumeof both the TV and the system." 5,1 OH (channel) audio is available when the TV is connected to an external device supporting 5.1 OH." When the receiver (amplifier or DVD home theater) is set to on, you can hear sound output from the TV'soptical jack. When the TV is receiving a DTV signal, the TV will send 5,1 OH sound to the amplifier or DVDhome theater, When the source is a digital component such as a DVD / Blu-ray player / cable box / STB(Set-Top-Box) satellite receiver and is connected to the TV via HDMI, only 2 OH audio will be heard from theamplifier or DVD home theater. If you want to hear 5,1 CH audio, connect the digital audio out jack from yourDVD / Blu-ray player / cable box / STB satellite receiver directly to an amplifier or home theater.Englishii