Audio decoder having a bandwidth extension module with an energy adjusting module

An audio decoder configured to produce an audio signal from a bitstream comprising audio frames, the audio decoder comprising:

• a core band decoding module configured to derive a directly decoded core band audio signal from the bitstream;
• a bandwidth extension module configured to derive a parametrically decoded bandwidth extension audio signal from the core band audio signal and from the bitstream, wherein the bandwidth extension audio signal is based on a frequency domain signal comprising at least one frequency band;
• and
• a combiner configured to combine the core band audio signal and the bandwidth extension audio signal so as to produce the audio signal;
• wherein the bandwidth extension module comprises an energy adjusting module being configured in such way that in a current audio frame in which an audio frame loss occurs, an adjusted signal energy for the current audio frame for the at least one frequency band is set
• based on a current gain factor for the current audio frame, wherein the current gain factor is derived from a gain factor from a previous audio frame or from the bitstream, and
• based on an estimated signal energy for the at least one frequency band, wherein the estimated signal energy is derived from a spectrum of the current audio frame of the core band audio signal.