The one above the Civic usb port is AUX. AUX interface (auxiliary) refers to an audio input interface that can input audio from electronic audio devices including mp3(universal headphone jack). Aux, is the abbreviation of \"auxiliary\
Secondary network communication domain: These interfaces are typically provided on routing and Layer 3 or higher hardware from major network vendors. (Auxiliaryport) An AUX port is an asynchronous port primarily used for remote configuration, dial-up connections, and connections to modems via transceivers. Supports HardwareFlowControl. Secondary ports and console ports are usually placed together because of their different configuration environments.