Systems and methods for detecting divergence in an adaptive system

A non-transitory storage medium storing program code for detecting divergence or instability in a noise-cancellation system, the program code, being executed by a processor, comprising the steps of:

• determining a power of a component of an error signal at a first frequency, the component being correlated to a noise-cancellation signal, the noise-cancellation signal being produced by an adaptive filter and being configured to cancel noise within a predetermined volume when transduced into acoustic signal, wherein the error signal represents a magnitude of a residual noise within the predetermined volume;
• determining a time gradient of the power of the component of the error signal;
• and
• comparing a metric to a threshold, wherein the metric is based, at least in part, on a value of the time gradient of the power of the component of the error signal over a period of time.