Can anyone help? If I have 1 microphone connected to XLR input 1, and another connected to input 2, is it possible for the audio to be mixed and output together via HDMI so that the sound can be heard live from both microphones to left and right speakers, and yet still record onto the SD card on separate channels to give flexbility when editing later.

The manual seems to indicate that that you can mix the audio output to the AV and headphone jacks, but to the HDMI output, and the recorded audio is per the input channel mapping.