Weird fade out in signal decoded from 13.2kbps fixed-point encoded bitstream with HOA2/HOA3 input at 16kbps and -26LKFS

Basic info

• Float reference:
  • Encoder (float):00ba8bcd
  • Decoder (float):00ba8bcd
• Fixed point:
  • Encoder (fixed):24f29d12

Bug description

Bitrate: 13.2kbps

Input format: HOA2/3

Signal level: -26LKFS

DTX: False

Sample rate: 16kHz

Observations: Frequent brief fade out in signal decoded from fixed-point encoded bitstream, as illustrated in the plot below.

Ways to reproduce

Box folder: ...\Box_EXTERNAL_IVAS_BASOP_VERIFICATION\issues\issue-1198

Command lines: see cmds.txt in the above Box folder