The connected home theater system, audio receiver, or soundbar isn't set to properly decode the digital signal. The Digital audio out volume is set too low in the TV settings. The optical . HDMI-CEC handles that for HDMI cables, but for optical, you must pick up the soundbar remote and press “Input” or “Source” until you see “OPT,” “DIGITAL,” or “D-IN” on the display. Original content by hifireport. Your TV isn't set to a digital channel or playing a video encoded in 5. Optical audio is a popular method of transmitting high-quality audio signals through a digital connection. Understanding the basics of optical audio is essential for troubleshooting any. For some reason the audio output channel I had been using on my receiver suddenly stopped outputting in PCM, and I hadn't noticed because there wasn't an obvious way to turn it on or off. My solution wound up being to wire it up to a different output channel, which for whatever reason had PCM. I am Expert Russell, & I will try to give the right answer to your audio / TV / device question. I am typing your answer now and should be able to post it within about 6 or 7 minutes.
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