Unable to retrieve AudioTrack pointer for write

E/AndroidRuntime: FATAL EXCEPTION: Thread-18065
                  java.lang.IllegalStateException: Unable to retrieve AudioTrack pointer for write()
                  at android.media.AudioTrack.native_write_byte(Native Method)
                  at android.media.AudioTrack.write(AudioTrack.java:983)

推测是播放过程中，执行了AudioTrack.stop()，依然异步执行AudioTrack.write()导致，因此，在执行两个函数时做下同步，或者判断下是否已经stop，如果否，才去write数据。