What mean EXCEPTION thrown ('fmt?') origin by [self.backgroundMusicPlayer play];

When a i run a example in simulator trying to play background music using AVAudioPlayer

i got the next message in the log:

EXCEPTION thrown ('fmt?')

In the internet i saw that i need configure sound output from my mac mini to internal speaker but

in Preferences/Sound i don see that options.

Thank

What mean EXCEPTION thrown ('fmt?') origin by [self.backgroundMusicPlayer play];
 
 
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