Any Processing Sound Library Supporting .m4a?

I’m trying to create an interface to play and browse my music. Thing is, most of it is in .m4a, and neither the Sound library nor the Minim library seem to support that format.
All my music is either in .m4a or in .mp3, and all I need to be able to do is play, pause, change playback speed and/or skip forward/backward, although I wouldn’t loathe having more functions to play with. Is there any library you can think of that would suit my needs?

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