原因是：出现项目中加入了“断点”！  真特么逗～

The problem was I normally develop with a breakpoint set to "All Exceptions", and the actual exception thrown was __cxa_throw. Which apparently turns out to be in C++ libraries that are used to implement AVAudioPlayer. By changing the breakpoint to "All Objective-C Exceptions" the program ran fine. (This can be done by editing the breakpoint and changing the Exception field to Objective-C.

在  stackoverflow.com/ 网站上有相关bug解释！

  具体点看这  ----->   stackoverflow.com/search   膜拜大神！

把下图1所示的断点去掉就OK啦！

图1