But how does the AVR know that the audio is in the analog audio inputs? You specify which HDMI syncs with the analog input?
You should be able to assign some specific analog input to a specific HDMI input on the receiver, but then the question is why you don't just use the HDMI for both audio and video and let your receiver do the decoding.
Particularly if you use any kind of dsp such as used with subwoofers or room correction, it will all be resampled anyway.
I feel like I am possibly missing something.