I was hoping to get a discussion started on what you could accomplish using splitters or switch in a setup where HDMI-ARC is used.
Consider a general setup involving a source (streamer, cable/sat box, game console, etc) connected to video display (TV or projector) and audio equipment (Sonos Amp or Beam). HDMI cables are used to connect a source to a display and then again to connect the display to audio (two way communication). Splitters and switches can easily be used between source and display because it's one way communication, but what about between the display and the audio where two way communication takes place?
I would think that you could use a switch (or matrix) in this situation as long as the connection was always one display and one audio device at a particular time. Would two way communication work as expected or would the handshaking getting mixed up? Would it only work if the switching occurred between two idential devices on the audio side (2 Sonos amps for example) or two identical TVs?
If you placed a splitter in between the display and audio, what would occur. Splitting with one TV an 2 audio equipment would not work as the TV can't handshake with two different devices at the same time. I would guess that you get no audio from either speaker in this case. Even if you used a splitter that extract and audio signal to an optical output would not work. The audio is coming over ARC, not the normal HDMI pins, thus it would be extracting the wrong audio. Reversing the splitter is a little interesting as in the that case, you aren't splitting the ARC signal, but you'd be splitting the the video signal coming out of the Beam/Amp. You wouldn't hear any sound, but multiple displays would see the Sonos screen saver...which is completely useless.
So it seems like if you want to do any splitting, it can only be done between the source and display if you want to use HDMI ARC. However, if you want to use 2 different speakers, you'd have to have 2 different displays. If you don't want 2 displays, is there a cheap device that be used to imitate a display, taking in an hdmi signal and then communicate to audio over hdmi?