BASOP assert in MDCT-Stereo Stereo pre-processing with music signal

Basic info

• Fixed point:
  • Encoder (fixed):571ad39a

Bug description

With attached music item, a saturation assert happens during the stereo pre-processing for MDCT-Stereo at 48 kbps:

Assertion failed: (0), function L_add, file basop32.c, line 1661.
fish: Job 1, '/Users/knj/Documents/IVAS/ivas-…' terminated by signal SIGABRT (Abort)

Problem happens in frame 348 in the outer L_add call at lib_enc/ivas_mdct_core_enc_fx.c:902:

Ways to reproduce

Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-1480

./IVAS_cod_fx -stereo -dtx -max_band fb 48000 48 vogue_44.wav bit