I have now tested the script on Anki 2.1.47 and AnkiDroid 2.15.6, and it works for me on both.
The script requires at least version 2.1.36 to work on Anki desktop, as stated in the comments of the script. Also, please make sure to check the following:
Disable "Don't play audio automatically" in the deck option.
Uncomment myAudio.play(); at the last line of the script. (That is, delete // at the beginning of the line.)
In the above screenshot, the code that i have put is also visible. I am not sure why audit control (the button visible on the screenshot) is not working for me. It could be possible that I am committing some overlook.
It might be that the audio file in collection.media does not match the file name you entered in audio_file field. I have uploaded a sample deck so you can try it out.
In the field “audio_file”, I was having file name as [sound:file_name] similar to other types of decks, however here for this solution, just file_name is needed (without the brackets, sound, : etc.). I was not aware of it. Thank you.