[SOLVED] No audio on Big Sur

[Schlachtbank]

Hello, I installed Big Sur on my X79 system. Everything works flawlessly except for onboard audio. The problem is missing api-path for audio controller (no acpi-patch under HDEF in IOReg). On the Big Sur install guide of OpenCore there's a way to fix the issue, I should build an SSDT-BRG0 to point the pci-bridge to the kernel, but I don't know how to do it. Can someone help me?

EDIT:

I solved it using an SSDT found on the web

 

[Ryan Thomas]

Good Day

Would you mind sharing your EFI??
I have Clover 5126 working with Cat 10.15.7, but no luck with Big Sur.
Had OC working then It would not let me choose a startup disk??

Anyway perhaps You could share??

 

[mikeysteele]

Hello, I installed Big Sur on my X79 system. Everything works flawlessly except for onboard audio. The problem is missing api-path for audio controller (no acpi-patch under HDEF in IOReg). On the Big Sur install guide of OpenCore there's a way to fix the issue, I should build an SSDT-BRG0 to point the pci-bridge to the kernel, but I don't know how to do it. Can someone help me?

EDIT:

I solved it using an SSDT found on the web

Where did you find this SSDT?

 

[mikeysteele]

For anybody else with the same problem I created an SSDT with the following and it fixed it for me (Gigabyte X79-UD5)

DefinitionBlock ("", "SSDT", 2, "ACDT", "HDEF", 0x00000000)
{
    External (_SB_.PCI0, DeviceObj)

    Scope (\_SB.PCI0)
    {
        Device (HDEF)
        {
            Name (_ADR, 0x001B0000)  // _ADR: Address
        }
    }
}

@Schlachtbank - It's considered good etiquette to post the solution to your problem if you find it yourself as it might help others later.