Echo return loss is analyzed to determine if the near end connection of a communication link has hybrid induced echo. If the echo return loss is above a threshold value for a predetermined period, than no echo or very little echo is present. The lack of echo is treated as a four wire connection and the near end signal is processed accordingly. If the foreground and background filter update relationship indicates the presence of a hybrid or if the echo return loss drops below a second threshold, the condition of the near end signal is treated as a two wire hybrid induced echo. The analysis of the near end signal continues and treatment of the signal may switch between four wire and two wire any number of times during a communication link.