I just purchased an Onkyo TX-NR708 receiver. My cable box and Sony blu ray player both output HDMI. My Sharp LCD TV has HDMI input. I intend to run HDMI from the blu ray player to the Onkyo and HDMI from the cable box to the Onkyo. Then run HDMI from the Onkyo to the TV. My friend says I should also run optical digital audio from the blu ray player and cable box to the Onkyo for better sound. Does that sound right?