If I may, one way to do so is to create a video with only your audio file, like we see on YouTube, Vimeo and such. That way, you can import your audio as a video and check to get the control bar.
I will say that it's a weird omittion that audio files don't have control bars. What if I want my user to listen to a 5-minute interview as part of a question? I guess that I could link the interview to an external page, but still, the lack of control options for audio is odd.
There's also the idea to make your own control bar using assets, but whether you use a Wipe Left animation or a ball that travels along a line, you cannot have animation that lasts more than 59 seconds.