[4] The technology has been hailed as "the most significant development in audio forensics since Watergate.
"[4] However, according to a paper by Huijbregtse and Geradts, the ENF technique, although powerful, has significant limitations caused by ambiguity based on fixed frequency offsets during recording, and self-similarity within the mains frequency database, particularly for recordings shorter than 10 minutes.
As a result, the light intensity can carry the frequency fluctuation information to the visual sensor recordings in a similar way as the electromagnetic waves from the power transmission lines carry the ENF information to audio sensing mechanisms.
As a result, the matching between the two signals can be used to determine if the audio and visual track were recorded together or superimposed later.
[8] The distinctive electrical hums have been used to provide forensic verification of audio recordings, a process fully automated in the United Kingdom.