thunder72fr made a post in the PULSE RX580 ROM study thread about that he can get HDMI audio working properly in Mojave with just Lilu.kext and AppleALC.kext installed.
I further tested it on my own cMP and confirmed it can work. And the process is simpler than HDMIAudio.kext + AppleHDA.kext patch.
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HDMI / Displayport audio fix
I further tested it on my own cMP and confirmed it can work. And the process is simpler than HDMIAudio.kext + AppleHDA.kext patch.
HDMI / Displayport audio fix