Patent ID: 8223982

Claim:
A method for detecting a change in performance of a hearing prosthesis comprising an audio signal processing path, the method comprising: receiving sound; converting the received sound into an audio signal; determining, by the hearing prosthesis, first and second reference values of a selected characteristic of the audio signal at first and second frequency bands of the audio signal, respectively, during a reference time period, wherein the selected characteristic is indicative of the energy content of the audio signal; determining, by the hearing prosthesis, first and second test values of the selected characteristic of the audio signal at the first and second frequency bands, respectively, during a test time period; calculating a reference ratio based on a ratio of the first and second reference values; calculating a test ratio based on a ratio of the first and second test values; and determining whether degradation has occurred over time in the audio signal processing path of the hearing prosthesis based on a comparison of the reference ratio with the test ratio.