We would need details on the ARC to optical converter to help, I suspect. Many of those devices go one way, and not the other, it’s hard to know if that’s the issue here. Sonos adapter, for instance, goes the other way, optical to ARC, but not ARC to optical. 

The Ray has an optical input, not output. The tv outputs to the Ray’s input connection. 

As ​@Airgetlam requested we need info on the adapter you are using. BTW…there have been others with the same issue regarding a Samsung TV with no optical out. The solution has been to move up to a more expensive Samsung model if still within the return window.

Thanks everyone. Here is the adapter I bought. Unfortunately unable to return the smart monitor so would need to upgrade if can’t get it working. 
 

Adapter

Which model monitor? What is the source of your TV programming? Are you using a cable box? ROKU? AppleTV? Built-in TV App?

This adaptor alone is not useful. You’d need more ‘boxes” to support this adaptor.

Thanks for the info on the adapter!

Accordingly you need to do the following:

1. You’ll need two HDMI cables and one Optical cable
2. Remove the HDMI cable from the Samsung TV and the AV Source (Cable Box or Streaming Stick)
3. Connect the same HDMI cable to the Extractor’s HDMI input and the AV source HDMI output_you should now have the HDMI cable connected between the AV source and Extractor 
4. Connect the 2nd HDMI cable to the Extractor’s HDMI output and the Samsung HDMI input
5. Connect the Optical cable to the Extractor’s Optical output and the Ray Optical input
6. Set the audio input to Bitstream to start

Let’s us know the outcome.