diff --git a/src/core/libraries/audio/audioout.h b/src/core/libraries/audio/audioout.h
index 7fcc25095..ef1588954 100644
--- a/src/core/libraries/audio/audioout.h
+++ b/src/core/libraries/audio/audioout.h
@@ -181,5 +181,6 @@ int PS4_SYSV_ABI sceAudioOutSystemControlSet();
 int PS4_SYSV_ABI sceAudioOutSparkControlSetEqCoef();
 int PS4_SYSV_ABI sceAudioOutSetSystemDebugState();
 
+void AdjustVol();
 void RegisterlibSceAudioOut(Core::Loader::SymbolsResolver* sym);
 } // namespace Libraries::AudioOut