forget the high res issue.
the apple tv app just have to be the remote … controlling the mac that will play highres files like usually.
Monoprice sells a hdmi in adapter that outputs digital coax &!optical toslink out along with a pass thru hdmi out. Just connect your DAC and press go. I just bought one and its awesome
Yep. I bought one of these monoprice HDMI switches as well. Nice piece of equipment.