HDMI 1.4a compliant devices will use the HDMI cable for communication when bi direction mode is on, this mode is switched through HDMI control so the units know it time to talk to one another, VS. i send you receive.
You should have surround sound to prevent the loss of audio channels. Your audio stream is going to put the sound to non exist-ant speakers, resulting in you literally not hearing something because its sent to a speaker that does not exist.
to solve this problem hook it up right, get you rear channels, turn on HDMI control, and run your equipment to the receiver, NOT the tv. Video out from the receiver goes to the tv only!
any other way, and it just complicates things....
Or do as suggested and hookup the CD connection.