An audio encoder for encoding audio samples has a first time domain aliasing introducing encoder configured to decode audio samples in a first encoding domain and having a first framing rule, a start window and a stop window. The audio encoder further has a second encoder configured to encode samples in a second encoding domain and having a predetermined frame size number of audio samples, and a coding warm-up period number of audio samples, the second encoder having a different second framing rule, a frame of the second encoder being an encoded representation of a number of successive audio samples that is equal to the predetermined frame size number of audio samples. The audio encoder further has a controller switching from the first to the second encoder and for modifying the second framing rule or for modifying the start or the stop window of the first encoder.