The Roku Ultra had a separate optical digital audio output, but that feature was discontinued 2 or 3 years ago. They only way I know of to get a separate audio output with the current product line is to run the HDMI output through a device that can extract the audio from the HDMI signal and output it separately. https://www.amazon.com/s?k=hdmi+audio+extractor
Doug Roku Community Streaming ExpertI am not a Roku employee, only a user like you. Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Streaming Stick 3600
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