Fixing HDMI Audio Stuck at 100% on Hackintosh

If you’re running a Hackintosh using HDMI audio, you might’ve hit a super annoying issue:

👉 Audio is always at 100% and can’t be controlled

No keyboard keys, no macOS slider, no EFI tweak seems to help.

Source Jervi-writes article

The Usual (Failed) Fixes

All of classic Hackintosh stuff:

• Tweaking EFI / OpenCore
  


• Audio layout changes


• Patching AppleHDA


• Different framebuffer configs

Nothing worked. HDMI audio volume stayed locked at max.

The Unexpected Fix: MonitorControl

Turns out the fix wasn’t in EFI at all.

MonitorControl (yes, the app used for external display brightness) completely solved the issue.

Once installed:

• HDMI audio volume became adjustable


• Keyboard volume keys worked


• macOS volume slider finally did something


• No EFI changes needed

Why This Works (Probably)

HDMI audio is tied to the display, and macOS treats it differently than normal audio outputs.

MonitorControl hooks into display-level controls, which indirectly restores proper volume handling for HDMI audio on RX480.