A:Answer Hi IcedCorn. When the digital optical connection was developed, it was made to accommodate the digital audio standards at the time (mainly 2-channel CD playback). In addition, it also provided enough bandwidth space for basic Dolby Digital and DTS Digital Surround but did not include the bandwidth capacity for the more advanced 5.1/7.1 channel PCM, Dolby Digital Plus, Dolby TrueHD, Dolby Atmos, DTS-HD Master Audio, or DTS:X surround sound formats. If you want to pass those more advanced surround sound formats, you will need to go through the HDMI eArC port on the LG CX 65 inch Class 4K Smart OLED TV w/ AI ThinQ® (64.5'' Diag), Model # OLED65CXPUA. The advantage of being able to use the TV's internal speakers simultaneously with devices connected to the Optical Digital Audio Ports is that some people who have hearing impairments want to connect a pair of infrared headsets to the TV's Optical Digital Audio Out so they can hear the audio while other members of their household listen to the TV's internal speakers...^IFV