https://roundup.mplayerhq.hu/roundup/ffmpeg/issue245

Although this issue is/was closed, it still affects FFmpeg as of r13570.  In
this directory is "24-bit_96kHz_RICE2_pop.flac" which is a 24-bit 96kHz FLAC
file encoded with flac-1.2.1, 10 seconds in length.  There is a very audible pop
about midway through the track that is not present in its corresponding WAV
file when played with FFmpeg's internal FLAC decoder.

Hopefully this aids your team in fixing this bug.

Tracker username: jkaufman
E-mail: jkaufman@gmail.com