A common problem in audio forensics is the difficulty to
authenticate an audio recording. In this paper we provide a novel
and reliable solution to this problem by making use of a control
signal, visible and audible on the actual recording, yet ignored by
the listener, the TIC-TAC signal. We describe our live watermark
solution, we incorporate it in an integrity check algorithm and we
provide meaningful preliminary tests. Their results, computed in
terms of precision show an outstanding performance: 100%
detection rate for edited recordings by means of deleting/inserting
audio fragments longer than 5ms and 0% false alarm rate for
unedited recordings.