The HDMI usely has the sound on it as well, so you would run the HDMI to your receiver then to your projector.
What is the purpose of HDMI 1080p outputs in an A/V receiver. If I have a 5.1 channel home theater speaker system and a projector set up, will the output ever be needed? I always believed that I could just run the HDMI cables straight from my cable tuner to the projector, there would be no need to run it through the receiver.

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