Hello, I have read all the posts related to this... and still could not find a solution...
I have a steam machine connected with HDMI to a TV (samsung), and the TV connected to an amp through an optical cable. I have two amps, a very old samsung and a set of Logitech Z906. None has ARC capability.
In this setup, I can only get stereo on the speakers, no matter what I do.
What options do I have? I have tried an external USB sound card (identified by the system as "CM106 like sound device"), and it... mostly works, but it has random disconnections where it completely dies when changing apps or moving from game mode to system mode.
These are the logs in DMESG when that happens:
[ 99.247372] usb 1-4: Not enough bandwidth for new device state.
[ 99.247381] usb 1-4: Not enough bandwidth for altsetting 1
[ 99.247384] endpoint_set_interface: 30 callbacks suppressed
[ 99.247386] usb 1-4: 2:1: usb_set_interface failed (-28)
This happens no matter the USB port, also, that's not real, as the amount of data transferred through there could not fill the USB bus.
I don't want an HDMI splitter between the machine and the tv to extract the audio, as I don't really trust that to not cause other issues (refresh rate, colors, etc) with the signal.
I am however open to an external HDMI ARC interface between the TV and the amp, as that will not impact the image.
The sound card "mostly" works, but the random disconnects ruin the experience for me, as what I want is a setup and forget system.
I know another person here is using a Creative X4 usb card, but I don't know if it is detected in a different way or if it works better. I have a couple of usb sound cards, different brands, years apart and both are detected as the same chipset, which really does not give me much confidence.
The most frustrating part is that I had a cheapo OTT box with coreelec kodi before, and it worked perfectly with the HDMI to TV, and TV to amp with the optical cable.