There is provided a method for use by an echo canceller to detect an echo
path change and adjust to the echo path change. The method comprises
determining a first bulk delay using a SPARSE foreground adaptive filter;
configuring the foreground adaptive filter to an open-loop mode;
canceling the echo signal based on the first bulk delay using the
foreground adaptive filter; determining a second bulk delay of the echo
signal using a SPARSE background adaptive filter; configuring the
foreground adaptive filter to a closed-loop mode and continuing to cancel
the echo signal based on the first bulk delay; configuring the background
adaptive filter to the open-loop mode; measuring echo cancellation
performance of the foreground adaptive filter and the background adaptive
filter; and changing parameters of the foreground adaptive filter if the
echo cancellation performance of the background adaptive filter is better
than the foreground adaptive filter.