A method performed at an intercom terminal of a multi-point to multi-point intercom system comprising the steps of: a) obtaining a unique intercom terminal identifier; b) obtaining a list of available intercom sessions; c) sending a request including said intercom terminal identifier to an intercom server of the intercom system to join several intercom sessions at the same time, from the list of available intercom sessions; d) detecting unmixed audio packets sent via the intercom server, said unmixed audio packets coming from talking intercom terminals connected to said intercom sessions to which the intercom terminal is listening to, each unmixed audio packet comprising: - a header having an intercom terminal identifier associated with a participant of said intercom sessions; and - audio data; e) distributing the audio data into audio tracks according to their identifier; f) buffering audio data of each of the audio tracks distributed in step e) during a buffering time interval; g) summing audio data of the tracks that have been buffered in step f) to obtain an audio signal; h) capturing another audio signal from a capture device during a predetermined time interval; i) measuring an intensity of the other audio signal to obtain an intensity signal for said other audio signal; j) creating an audio packet comprising: - a header having the intercom terminal identifier and the intensity signal of step i); and - audio data derived from the audio signal; and k) sending the audio packet of step j) to an intercom server of the intercom system. a) obtaining a unique intercom terminal identifier; b) obtaining a list of available intercom sessions; c) sending a request including said intercom terminal identifier to an intercom server of the intercom system to join several intercom sessions at the same time, from the list of available intercom sessions; d) detecting unmixed audio packets sent via the intercom server, said unmixed audio packets coming from talking intercom terminals connected to said intercom sessions to which the intercom terminal is listening to, each unmixed audio packet comprising: - a header having an intercom terminal identifier associated with a participant of said intercom sessions; and - audio data; - a header having an intercom terminal identifier associated with a participant of said intercom sessions; and - audio data; e) distributing the audio data into audio tracks according to their identifier; f) buffering audio data of each of the audio tracks distributed in step e) during a buffering time interval; g) summing audio data of the tracks that have been buffered in step f) to obtain an audio signal; h) capturing another audio signal from a capture device during a predetermined time interval; i) measuring an intensity of the other audio signal to obtain an intensity signal for said other audio signal; j) creating an audio packet comprising: - a header having the intercom terminal identifier and the intensity signal of step i); and - audio data derived from the audio signal; and - a header having the intercom terminal identifier and the intensity signal of step i); and - audio data derived from the audio signal; and k) sending the audio packet of step j) to an intercom server of the intercom system.