I don't see much point in displaying audio files amongst the image files myself.
But if you want to display them together .... how about something a little nicer ? A musical note icon would be more visually explanatory.
The 3 dots https://line25.com/articles/10-html-entity-crimes-you-really-shouldnt-commit
The 3 dots is an ellipsis and is a pause in a sentence. Not an intuitive icon for an audio file. IMO.