MediaPlayer play only first seconds of my android studio audio with kotlin

For what you describe "it lasts 2 or 3 seconds and stops", if the playback does not finish, the problem is surely the audio file, it probably has an error , specifically you must ensure that it uses the appropriate codecs

Android: Supported Formats

To check specifically what the error is, I suggest you use the listenerOnErrorListener , where you can print and check what type of error you get when an error occurs.

        mp!!.setOnErrorListener { mp, what, extra ->
            Toast.makeText(this,"Ocurrio un error reproducción mp: ${mp}\nwhat: ${what}\nextra: $extra" ,Toast.LENGTH_SHORT).show()
            false
        }

I also suggest you also use the listener OnCompletionListener, which will tell you when I have completely finished playing the media file.

    mp!!.setOnCompletionListener {
        Toast.makeText(this,"Finaliza reproducción",Toast.LENGTH_SHORT).show()
    }

Kotlin: How to play audio using MediaPlayer?

        val mp = MediaPlayer.create(this, R.raw.suspenso)
        mp!!.setOnPreparedListener {
            mp.setVolume(100F, 100F)
            mp.start()
            Log.i(TAG, "Inicia reproducción")
        }
        mp!!.setOnCompletionListener {
            Toast.makeText(this,"Finaliza reproducción",Toast.LENGTH_SHORT).show()
            Log.i(TAG, "Finaliza reproducción")
        }
        mp!!.setOnErrorListener { mp, what, extra ->
            Toast.makeText(this,"Ocurrio un error reproducción mp: ${mp}\nwhat: ${what}\nextra: $extra" ,Toast.LENGTH_SHORT).show()
            Log.i(TAG, "ERROR mp: ${mp}\nwhat: ${what}\nextra: $extra")
            false
        }

After searching and trying several examples I have found the solution.

For it to MediaPlayerwork properly it needs to be initialized outside the context of a function, as if it were a property of the class.

If you look at my code, the initialization of MediaPlayeris inside the onCreate. Big mistake!

The solution is the next:

class MainActivity : AppCompatActivity() {
    private var mPlayer: MediaPlayer? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        mPlayer = MediaPlayer.create(this, R.raw.musica_de_fondo)
        mPlayer?.start()
    }
}