The HDMI Forum, responsible for the HDMI specification, continues to stonewall open source. Valve’s Steam Machine theoretically supports HDMI 2.1, but the mini-PC is software-limited to HDMI 2.0. As a result, more than 60 frames per second at 4K resolution are only possible with limitations.
should be able to with hdmi arc, not sure 100% tho but it seems like you could tell the projector where to send the audio, i know you can with tvs and hdmi arc. worst case scenario you do dp in to the projector and hope valve has stereo or optical out to go into reciever
Yes, I have recognised, that if a speaker is connected on the HDMI-ARC port, it will play audio from other input sources to TV still on those speakers. But in my setup, other input sources are HDMI as well…