how to prevent creating of menu/chapter?

Question

I'm using this simple command for re-encoding my audio tracks

ffmpeg.exe -i "SOURCE.mp4" -acodec pcm_f32le -f wav - | neroAacEnc.exe -ignorelength -q 1 -cbr 80000 -lc -if - -of "out.aac"

and I noticed that out.aac contains "Menu" section which translates as "Chapter" track if I throw it into MKVToolnix / MKVmerge

Mediainfo:

MKVToolnix:

content of Chapter / Menu track (extracted as xml):

<?xml version="1.0"?>
<!-- <!DOCTYPE Chapters SYSTEM "matroskachapters.dtd"> -->
<Chapters>
  <EditionEntry>
    <EditionFlagHidden>0</EditionFlagHidden>
    <EditionFlagDefault>0</EditionFlagDefault>
    <EditionUID>7321170048711332010</EditionUID>
    <ChapterAtom>
      <ChapterUID>8251239689279814674</ChapterUID>
      <ChapterTimeStart>00:00:00.059000000</ChapterTimeStart>
      <ChapterFlagHidden>0</ChapterFlagHidden>
      <ChapterFlagEnabled>1</ChapterFlagEnabled>
      <ChapterDisplay>
        <ChapterString>00:00:00.059</ChapterString>
        <ChapterLanguage>eng</ChapterLanguage>
      </ChapterDisplay>
    </ChapterAtom>
  </EditionEntry>
</Chapters>

Q: I would like to know why this happens and how can I prevent it.
(this happens even with -flags +bitexact and / or -map_chapters -1)