there are a few out there now that will handle multiple hdmi out with audio to match. it just depends on how much you want to spend. The onkyo 838 has two video zones and a third audio zone.
If you want wired whole house audio inexpensively and relatively easy to install, the channel vision a-bus system works well to give you audio in each room hanging off one of the zones on the receiver or a stereo output from linuxmce. then you have a local volume control in each room. you can't control the volume with the orbiters but it is very simple for just background music or jamming cleaning music (WAF)