1. A computer-implemented method comprising: receiving a sample of an audio signal; determining that at least one portion of the sample includes an audio characteristic representing silence; generating a modified sample from the sample that includes first additive audio in the at least one portion of the sample including silence, where the first additive audio is above an audio characteristic threshold; generating a test audio fingerprint based on the modified sample that includes the first additive audio; comparing the test audio fingerprint with each of a set of candidate reference audio fingerprints previously generated from one or more reference audio signals; determining that the test audio fingerprint generated based on the first additive audio does not match a first candidate reference audio fingerprint of the set of the candidate reference audio fingerprints; determining that the test audio fingerprint does match a second candidate reference audio fingerprint of the set of the candidate reference audio fingerprints; and storing an association between information associated with the sample of the audio signal and information associated with the second candidate reference audio fingerprint.