Hi @kanuuker
Welcome to the Roku Community!
We understand that you are having confusion with HDMI ARC and non-HDMI ARC. The HDMI ARC connection provides a number of benefits over the digital audio output.
- Less clutter: With a single cable, HDMI ARC uses two-way communication to send sound to your AVR or soundbar while simultaneously sending pictures to your Roku TV. There is no need for separate audio and video cables.
- Control other devices: Using only your Roku TV remote, you can control aspects of your home theater, like adjusting the volume and muting the sound.
- Support for more surround sound formats: The HDMI ARC connection supports the same formats as the digital audio output, but with greater throughput, it also supports advanced formats like Dolby Digital Plus and Dolby Atmos. The S/PDIF connection is limited to 2 channels of uncompressed stereo sound (PCM) or 5.1 channels of compressed surround sound (Dolby Digital or DTS).
You can check out this support article: How to connect a surround sound system to your Roku TV
See if it helps; keep us posted so we can assist further if needed.
Best regards,
Arvy
Marc
Roku Community Moderator