以下代码为什么不播放声音？它为play（）返回“ true”，但我听不到任何声音。

    let path = "/Users/account/Music/sound.mp3";
    let fileURL = NSURL(fileURLWithPath: path)
    var Player = AVAudioPlayer(contentsOfURL:fileURL, error:nil);

    Player.delegate = self;
    Player.prepareToPlay();
    Player.volume = 1.0;
    var res = Player.play();
    println(res);

如果我改用以下代码，则可以听到声音。

    var inFileURL:CFURL = fileURL!;
    var mySound = UnsafeMutablePointer<SystemSoundID>.alloc(sizeof(SystemSoundID));
    AudioServicesCreateSystemSoundID(inFileURL, mySound);
    AudioServicesPlaySystemSound(mySound.memory)

• OS X优胜美地10.10.3
• Xcode 6.2