Encoder-related BWE issues for OMASA ISM1MASA2 at 48kbps for -16LKFS input

Basic info

• Float reference:
  • Encoder (float):
  • Decoder (float):
• Fixed point:
  • Encoder (fixed):dcf1701a
  • Decoder (fixed):dcf1701a

Bug description

There are BWE issues causing audible energy drops to ambience noise degrading the overall quality. Issue happens for ISM1MASA2 case at 48kbps mainly for input -16LKFS. It does not happen for -26LKFS input.

Plot for FX-FX

Plot for FLT-FLT

Plot for FLT-FX

Ways to reproduce

Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\basop-issue-2017

./IVAS_cod -ism_masa 1 2 cat1_concatenated.wav.0.csv cat1_concatenated.wav.met 48000 48 cat1_concatenated.wav cat1_concatenated_48kbps_ISM1_MASA2.192
./IVAS_dec binaural 48 cat1_concatenated_48kbps_ISM1_MASA2.192 cat1_concatenated_48kbps_ISM1_MASA2.wav