### Basic info - Commit SHA: cf46c019ea5564e7a1902b525a687a536a0c54d2 - Platform: Windows and Linux ### Bug description Running ISM 4 with an artificial signal of one noise signal and the rest zeroes, the output signal looks and sounds strange. It seems like the spectrum above 6.4 kHz is somehow repeated.  ### Ways to reproduce ``` git checkout cf46c019ea5564e7a1902b525a687a536a0c54d2 make -j IVAS_cod -ism 4 NULL NULL NULL NULL 128000 48 ism4_1noise.wav bit IVAS_dec EXT 48 bit out.wav ```  <!--- Below are labels that will be added but are not shown in description. This is a template to help fill them. Add further information to the first row and remove and add labels as necessary. -->