I've made further progress, and the problem seems to be how Roon Bridge interacts with the Integrated Audio Kernel Mode.
When Kernel Mode is active, I see two devices in Roon (one for each HDMI output), but neither of them show the correct information regarding channel layout, and playback fails.
When I activate Firmware Mode, I see four devices (two for "Kernel" and two for "Firmware"), and the two new devices created through Firmware mode show the correct information and playback works!
The problem is that with Firmware mode on, no other renderer works and I get the following error when trying to play anything but Roon through HDMI.
When Kernel Mode is active, I see two devices in Roon (one for each HDMI output), but neither of them show the correct information regarding channel layout, and playback fails.
When I activate Firmware Mode, I see four devices (two for "Kernel" and two for "Firmware"), and the two new devices created through Firmware mode show the correct information and playback works!
The problem is that with Firmware mode on, no other renderer works and I get the following error when trying to play anything but Roon through HDMI.
