Large differences between BASOP and float after application of the upmix ACELP BWE in ivas_sba_dirac_stereo_dec()

Basic info

• Float reference:
  • Encoder (float):c11c21eb
  • Decoder (float):c11c21eb
• Fixed point:
  • Encoder (fixed):43ca007c
  • Decoder (fixed):43ca007c

Bug description

For Frame 2276, hSCE->save_hb_synth (outputHB) differs significantly in ivas_sba_dirac_stereo_dec() between float an BASOP. After the application of the upmix ACELP BWE, output is significantly different, and causes the peak error at about 45,5 sec. There are similar peak errors before, not that high, but maybe caused by the same issue.

Differences output float vs. BASOP

Differences "outputHB" of ivas_core_dec()

Ways to reproduce

IVAS_dec MONO 48ltv48_FOA.wav_SBA_at_32_kbps_48kHz_in_48kHz_out_MONO_out_DTX.192 dec_basop.wav

Bitstream is the same as in issue #1967