Intel iEi Motherboard A300 - Manual (Page 187)

A300 Motherboard
Connector Sensing:- Realtek ALC655 detects if an audio device is plugged
into the wrong connector. If an incorrect device is plugged in a warning
message appears.
HRTF Demo:- Adjust HRTF (Head Related Transfer Functions) 3D positional
audio here before running 3D applications.
Microphone Effect:- Microphone noise suppression is enabled in this menu.
General:- General information about the installed AC’97 audio configuration
utility is listed here.
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