coreconvert m4b (Audio Book) option to specify bitrate?

[CarryWise]

The following command converts using a 224 kbps, in spite of the specified bitrate. Any idea what's wrong?

"C:\Program Files\dBpoweramp\CoreConverter.exe" -infile="D:\MP3 Audiobooks\Disc-1\Track-01.mp3" -outfile="D:\MP3 Audiobooks\Disc-1\Track-01.m4b" -convert_to="m4b (Audio Book)" -bitrate 64

[CarryWise]

Ok, I followed the documentation on creating a CD ripper profile and using regedit to get these options to control the bitrate:

-cli_encoder="C:\Program Files\dBpoweramp\encoder\m4b (Audio Book)\fdkaac.exe" -cli_cmd="-b 64000 -p 2 --ignorelength -S -o {qt}[outfile]{qt} - " -selection="1,7,0"