In a communication system (100), a first echo return loss through communication system (100) associated with a first call connection between a caller (111) and a first caller (114) is estimated. A second echo return loss associated with a second call connection between caller (111) and a second caller (112) is estimated. The call connection may be switching from the first call connection to the second call connection after estimating the first echo return loss, and from the second call connection to the first call connection after estimating the second echo return loss. Echo generated in the first call connection is cancelled based on at least the first echo return loss by an echo canceller in communication system (100) after switching from the second call connection to the first call connection.