I have a JVC LXT-32X667 TV. It has worked great for years.
I also have RCA Home Theater RT2770.
For years I have fed the TV Headphone output to the Line-In of the RCA. The RCA Stereo Out has a fixed volume. The headphone out is variable which makes the use of one Remote Control easier.
I decided to use a TOSLINK and connect the JVC TV to the RCA Home Theater optically. However I get nothing. Setting the Digital Audio Out to Dolby and PCM makes no difference.
I have FiOS and a Motorola QIP2500-3 STB and when I move the TOSLINK from the TV to the STB I do get sound. Move it back to the TV and I get nothing.
It does not make a difference if the TV is showing TV Content or if I hook my Latitude E5430 HDMI to the TV and use it as an extended screen and play any content via VLC Player.
I looked at everything on the JVC TV and I can see no reason why I get no audio out via Optical S/PDIF.
This old thread seems "similar". https://www.ecoustics.com/electronics/forum/home-video/572321.html
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