1. An acoustic echo path change detection apparatus comprising: a time domain path change detection functionality in communication with an acoustic echo canceller, said time domain path change detection functionality arranged to: detect a change in a near-end acoustic echo path responsive to a time domain analysis of a near-end signal and a signal output by the acoustic echo canceller; and output an indication of said detected change, a frequency domain path change detection functionality in communication with the acoustic echo canceller, said frequency domain path change detection functionality arranged to: detect a change in the near-end acoustic echo path responsive to a frequency domain analysis of a far-end signal and the signal output by the acoustic echo canceller; and output an indication of said detected change, and a combination path change detection functionality arranged to: determine a first function of said output indication of said time domain path change detection functionality and said output indication of said frequency domain path change detection functionality; and output said determined first function.