I have an HV20 and Denon 4806 Receiver. I get no audio (but Video is fine) from the hdmi connection from the HV20. I called Canon..they had no suggestions. I then exchanged the camera...still no luck with a new HV20.
This should not be a configuration issue, I can unplug the HDMI plug from my tivo and plug it into the HV20 with the same result: Video but no audio.