Serious clicks in ISM + FER at higher bitrates

• Encoder (float): d18cbee3 (ivas-float-update)
• Decoder: 9bae8e35 (current main)

Bug description

Serious clicks occur in ISM + FER conditions for higher bitrates with a range of bandwidth limitations resulting in high MLD, ~40.

For ISM +1 16 kHz input + FER, the issue is present for all bandwidth limitation configurations (WB, FB, SWB and bandwidth switching) at bitrates 64 kbps, 96 kbps and 128 kbps.

For ISM +1 32 kHz and 48 kHz input + FER, the clicks occur at WB and bandwidth switching at bitrates 64 kbps, 96 kbps and 128 kbps.

For ISM +2 16 kHz input + FER, all bandwidth limitation configurations at bitrates 96 kbps and 128 kbps.

For ISM +2 32 kHz and 48 kHz input + FER, WB and bandwidth switching at bitrates 96 kbps and 128 kbps.

For ISM +3 16 kHz input + FER, all bandwidth limitation configurations at bitrate 256 kbps.

For ISM +3 32 kHz and 48 kHz input + FER, WB and bandwidth switching at bitrate 256 kbps.

For ISM +4 16 kHz input + FER, all bandwidth limitation configurations at bitrates 256 kbps and 512 kbps.

For ISM +4 32 kHz and 48 kHz input + FER, WB and bandwidth switching at bitrates 256 kbps and 512 kbps.

Floating-point:

BASOP:

Ways to reproduce

 ./IVAS_cod_ref.exe -max_band WB -ism +3 scripts/testv/stvISM1.csv scripts/testv/stvISM2.csv scripts/testv/stvISM3.csv 256000 48 scripts/testv/stv3ISM48s.wav bit

 eid-xor -fer -vbr -bs g192 -ep g192 bit input/fer10%.192 bit_error

 ./IVAS_dec.exe BINAURAL 48 bit_error outIsm3.wav