A linear full duplex system and method for acoustic echo cancellation is disclosed. In one embodiment, a method includes calculating a residual echo after subtraction of an echo estimate from a near end signal associated with a communication, refining a far end and a residual signal associated with the communication, updating, based on the far end signal, the echo estimate of an echo associated with the communication, subtracting the echo from the near end signal based on the echo estimate to cancel the echo associated with the communication, updating, based on the refined far end and refined residual signal, the adaptive filter module used for echo estimation, and detecting a steady state and, during the steady state, dynamically detecting internal substates and switching between the internal substates and detecting and managing double talk associated with the communication.