Nvidia HDMI sound card not detected

[Davincible]

Fixed with this solution:

No sound over HDMI after Nvidia driver update

If you have the hybrid config installed in mhwd: open /etc/udev/rules.d/90-mhwd-prime-powermanagement.rules and put # in front of this line: ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x040300", ATTR{remove}="1" and then reboot.

Why is that even enabled by default …