I am trying to setup my Roku Streambar Pro. It is connected to my 86" (2 year old) Smart LG TV via HDMI port 4 (I do not have an ARC port available) - And, I have it connected via the Optical cable. I bought the Soundbar ONLY to improve the audio of my TV (i.e., I don't need to use any of the ROKU Streaming Services). My TV audio output is set to: Optical + Internal Speaker . The Soundbar works great when the TV input is set to HDMI 4. The problem is when I switch to HDMI 1 (where my set top cable box is connected) I get NO sound from the Soundbar.
The audio on hdmi 4 is coming via the hdmi cable, when using other devices connected to the tv the sound has to travel via the optical cable to the soundbar. So are you sure the optical cable is seated properly on either end? And optical cables can go bad, its glass if bent too far it can break.
Edmund Roku Community Streaming Expert
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