Click-like artifact in stereo speech item at 48kbps with fx encoder

Basic info

• Float reference:
  • Decoder (float): d3f01fcf
• Fixed point:
  • Encoder (fixed): 338a38b9

Bug description

There are click-like artifacts happening in this stereo item with the fx encoder. The item itself is repeated once and in both repetitions a similar artifact is seen. The locations are 1.12s and 8.70s. The floating-point reference encoder does not cause either of these two artifacts. See screenshots below:

This item is known to trigger the kernel-switching in the MDCT-Stereo core coder, maybe that part should be checked.

Ways to reproduce

Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-1536

./IVAS_cod_fx -stereo 48000 48 item7245_repeated.wav bit
./IVAS_dec_flt_ref stereo 48 bit out.wav