Android's Voice Recorder can't detect my file ?

[AC Question]

Hello.

So I have a file right now that I converted to .m4a. But no matter what I do, the Voice Recorder won't read it, so I just can't listen to it. And I could listen to it with VLC or whatever but the Voice Recorder has the +5s or -5s skip which is extremely useful.

So why can't this damn recorder detect my file ? Thanks