Can we add a sonic brand (ringtone) to a survey theme?

Our company has created a myriad of tones and songs that include a sonic brand. I would like to know if we can add them to our surveys. I have been able to autoplay them on End of Survey messages, but in order for that to work we have to add the code to all the translations. Is there a way to add the mp3 file to a theme, similar to how a .jpg or .gif is added to a theme?