I'm afraid your aproach has some drawbacks. I've made you a script for what you requested:

if [[ ${#} -lt 1 || ! -d ${1} ]]; then

    echo "Calling failed, try with something like"

    echo "${0} ~/Music"

    exit 1

fi 



while IFS= read -r -d $'\0' file; do

  a[i++]="$file"        # or however you want to process each file

done < <(find "${1}" -name "*.mp3" -print0)

mplayer -shuffle "${a[@]}"

Place that in a file like shuffle_play

chmod +x shuffle_play

mv shuffle_play /usr/bin/ # as root!

Then give it a try with:

shuffle_play ~/Music

This will only play your mp3 files. If you need other file formats you can modify the script yourself or ask me to do it :)

Regards

It's a little trickier than that ;)

done < <(find "${1}" -name "*.mp3" -o -name "*.ogg" -o -name "*.flac" -print0)

That should do the trick!

Regards