Unlike audio settings for other devices, settings for the HD PVR are selected in the EyeTV Setup Assistant, rather than the Devices section of the EyeTV Preferences.

Re-run the Setup Assistant until you get to the screen shown in the image below, and select the S/PDIF Optical audio setting.

You should be able to continue to the next screen and then quit the Setup Assistant rather than going through the entire setup, and the S/PDIF selection should be remembered.

If you need support regarding your EyeTV product please do not hesitate to contact us following this link.

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https://www.geniatech.eu/faq/how-do-i-change-eyetvs-audio-input-to-use-spdif-on-the-hd-pvr/ How do I change EyeTV’s audio input to use S/PDIF on the HD PVR?