McMASA full BASOP path with rate switching has a spike not present in interop cases

Basic info

• Float reference:
  • Encoder (float): 006def7e
  • Decoder (float): 006def7e
• Fixed point:
  • Encoder (fixed): bf9ba511
  • Decoder (fixed): bf9ba511

Bug description

Using the provided command line and the inputs, there is somewhat interestingly a spike only in the BASOP-enc to BASOP-dec path while nothing similar shows up when one of the parts is float.

One note is that the input signal is selection test material which has been attenuated by about 11 dB (divided by 3.548133892335755 to be exact). If this attenuation is reverted at the end (e.g. for wav-diff), then the spike will clip and cause huge MLD value.

I also do not remember seeing this issue before. E.g., my previous similar run was for commit f1458362 and did not show this.

Ways to reproduce

Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-xxxx

Files in box

IVAS_cod -mc 7_1_4 -max_band fb mcmasa_7_1_4_techs_start_48k_20frames.bin 48 bm3aa1s16.wav test_1033.bs
IVAS_dec BINAURAL 48 test_1033.bs 1033_bm3aa1s16.wav_mcmasa_7_1_4_techs_start_48k_20frames_48-48___BINAURAL.wav