Abstract: The present invention provides an improved determination of an acoustic coupling between a loudspeaker (110) and a microphone (120), which results in a better estimate of the acoustic coupling during double talk. This is achieved in a device (100) for determining an acoustic coupling between a far-end talker signal (101) as produced by the loudspeaker (110) and a combined signal (102), which comprises an echo of the far-end talker signal and a near-end talker signal, as picked up by the microphone (120), in which the acoustic coupling is derived from a ratio of changes in an envelope of the combined signal (102) to changes in the envelope of the far-end talker signal (101) in a predetermined time interval. In this way the systematic error during double talk (an estimation of the acoustic coupling that is too large) is not present anymore or at least strongly reduced.