I am getting no sound when on TV sound.

Yes, to get sound from your Roku TV to your receiver when using the TV's built-in apps (such as switching to TV sound), you might need more than just RCA cables. RCA cables only carry analog audio signals, and many modern devices, including Roku TVs, use digital audio signals for better quality.
Here's what you can do to ensure you're getting sound from your Roku TV to your receiver:

1. Check Audio Settings on Roku TV:
   • Go to your Roku TV's settings menu.
   • Look for the audio settings section.
   • Make sure the audio output is set to the correct option for your receiver. This is usually HDMI ARC (Audio Return Channel) or Optical audio.
2. Use HDMI Cable with ARC Support:
   • If your receiver and TV support HDMI ARC, connect an HDMI cable between the ARC HDMI port on your TV and the ARC HDMI port on your receiver.
   • Ensure that the HDMI input on your receiver corresponds to the HDMI ARC output on your TV.
   • In the TV's audio settings, select HDMI ARC as the audio output.
3. Use Optical Cable (if no HDMI ARC):
   • If your TV and receiver don't support HDMI ARC, you can use an optical audio cable (Toslink cable).
   • Connect one end of the optical cable to the optical audio output on your TV.
   • Connect the other end to the optical audio input on your receiver.
   • In the TV's audio settings, select optical audio as the audio output.
4. Configure Receiver Settings:
   • Ensure that your receiver is set to the correct input source for audio. For example, if you're using HDMI ARC, select the corresponding HDMI input on your receiver.
5. TV App and Volume Settings:
   • When using apps on your Roku TV, make sure the volume is turned up and not muted within the app itself.
   • Adjust the TV's volume settings to an appropriate level that allows your receiver to amplify the sound effectively.
6. Test with Different Content:
   • Test the setup with different apps on your Roku TV to ensure that the issue is not specific to a certain app.

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