The invention relates to an encoder (1) comprising an input (1.2) for inputting frames of an audio signal in a frequency band, an analysis filter (1.3) for dividing the frequency band into at least a lower frequency band and a higher frequency band, a first encoding block (1.4.1) for encoding the audio signals of the lower frequency band, a second encoding block (1.4.2) for encoding the audio signals of the higher frequency band, and a mode selector for selecting operating mode for the encoder among at least a first mode and a second mode. In the first mode signals only on the lower frequency band are encoded, and in the second mode signals on both the lower and higher frequency band are encoded. The encoder (1) further comprises a scaler to control the second encoding block (1.4.2) to gradually change the encoding properties of the second encoding block (1.4.2) in connection with a change in the operating mode of the encoder. The invention also relates to a device, a decoder, a method, a module, a computer program product, and a signal.