<key>hda-gfx</key> <string>onboard-1</string> <key>device-type</key> <string>Intel HD Audio HDMI</string> Then, ensure your AppleALC.kext is updated. You may also need to add alcdelay=1000 to your boot-args to force macOS to wait for the HDMI audio chip to initialize. Sometimes HDMI audio works, then stops after sleep.

Or, for AMD: -radcodec

You plug in your external monitor, your TV, or your second display, and… nothing. A black screen. A pink tint. Glitchy artifacts. Or worse, the system freezes the moment you connect the cable.