for f in "/volume1/music/\!\!Hoerbuecher\ MP3/1/*.mp3"; 
#do ffmpeg -i "$f" -qscale 0 "${f%.mp3}.m4a"; 
do ffmpeg -i "$f" -q:v "${f%.mp3}.m4a"; 
mv "${f%.mp3}.m4a" "${f%.mp3}.m4b"; 
done;