1. A method of removing echo, the method comprising: outputting an audio signal; receiving an audio signal, wherein the received audio signal includes echo resulting from said outputted audio signal; determining a first model estimate of the echo in the received audio signal using a first model based on the outputted audio signal and the received audio signal; determining a second model estimate of the echo in the received audio signal using a second model based on the outputted audio signal; determining a first accuracy value of the first model according to a model accuracy measure; determining a second accuracy value of the second model according to the model accuracy measure; determining if the first model is more accurate than the second model based on a comparison of the first accuracy value and the second accuracy value and selectively updating the second model based on said comparison; and using only the second model estimate of the echo to remove the echo in the received audio signal.