A method and apparatus, locally inserts non-noise background audio information (104), such as music or other suitable information, as comfort audio information with other audio information (110), such as voice, to produce a combined audio signal (112) containing non-noise comfort audio. The combined...http://www.google.com.hk/patents/US20040125965?utm_source=gb-gplus-share專利 US20040125965 - Method and apparatus for providing background audio during a communication session
