4. The method of claim 1 , wherein (B) comprises: replacing the identified first portion with a second audio signal portion that does not include personally identifying information.
4. The method of claim 1 , wherein (B) comprises: replacing the identified first portion with a second audio signal portion that does not include personally identifying information. 6. The method of claim 4 , wherein replacing the identified first portion comprises replacing the identified first portion with an audio signal representing a type of concept represented by the identified first portion.