Processing text leads to looped speech output

[hartmutobendorf]

When entering shell-type input into the Web UI, the resulting voice output contains a number of loops at the end of the sound file.

To reproduce:
docker run -it -p 5002:5002 synesthesiam/mozillatts:en

enter:
$ for i in ("mark.mp4" "john.mp4"); do convert $i ${i:4}; done

resulting wav file converted to mp3
error.zip