A scheme for localizing a wireless user equipment (UE) device's relative position with respect to a spatial configuration based on audio signatures received via a multi-channel audio system, e.g., an audio system of a vehicle or home entertainment system. The wireless UE device is configured to capture the audio signatures from a head unit that are placed in an out-of-hearing band, wherein the audio signatures comprise a single beep per channel that is separately detectable and are simultaneously transmitted by the head unit to the speaker channels. The wireless UE device includes a persistent memory module having program instructions for processing the captured signal including the out-of-band signatures in order to compute time delays. A localization module is configured to estimate the wireless UE device's relative position based on the time delays associated with respective speaker channels.