Recently purchased the Streambar 9102R. Attempting to use the optical audio input with not success. Apparently there is no setting in the software to control the audio input once the device is configured. You can indicate if your TV supports HDMI ARC during setup but that seems to be the only time. I did indicate that my TV does NOT support HDMI ARC but the Streambar will still not play audio through the optical input. I've tried two different audio sources to no avail. The optical cable is lit. There is no light coming from the Streambar optical input? Any suggestions? I've spent hours playing with this.
I don't have a Streambar, but I'll throw out a few thoughts. Have you ever used the optical output from your TV? Have you gone through the TV settings to see if the output has to be enabled? You already said you tried multiple sources, but do you have another sound device that uses optical to verify that the sources are working? It's been a while since I've used anything with an optical connection, but the first time I did I didn't get any sound and I was surprised at how far I had to insert the cable. I thought the cable was connected at both ends, but it clearly wasn't. You should be able to see a light coming from the opposite end of the cable that's connected to the TV, but nothing from the Streambar input.
Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution." If you appreciate my answer, maybe give me a Kudo.