I've decided to go with a new receiver, an AV Receiver
RX-A700 by Yamaha that has HDMI V1.4a. I'll use my existing Onkyo Amp M-282 and run it with a Niles SSVC4 speaker selector to send audio to 3 other rooms. I'll also add a Logitech Harmony 900 remote which will also control the master volume of the 2nd room source running through the Onkyo.