Ios 用音频录制视频

我要创建一个应用程序，我要用音频录制视频，然后播放它

为此，我在代码中使用了AVCaptureManager

在这里，如果视频是大约10秒，音频和视频播放，它的工作良好

但如果我录制的视频超过10秒，则只能无声播放视频（没有声音播放）

这是我的密码

    - (void)startRecording
    {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,           NSUserDomainMask, YES);         
NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents folder
NSString *dataPath = [documentsDirectory stringByAppendingPathComponent:@"/GeneralInstruction"];

NSError *error;
if (![[NSFileManager defaultManager] fileExistsAtPath:dataPath])
    [[NSFileManager defaultManager] createDirectoryAtPath:dataPath withIntermediateDirectories:NO attributes:nil error:&error]; //Create folder
NSDate *time = [NSDate date];
NSDateFormatter* df = [NSDateFormatter new];
[df setDateFormat:@"ddMMyyyyhhmmss"];
NSString *timeString = [df stringFromDate:time];
NSString *myUniqueNames = [NSString stringWithFormat:@"%@", timeString];

NSString *myUniqueName = [NSString stringWithFormat:@"file://%@/%@.mp4",dataPath, myUniqueNames];

[self.fileOutput startRecordingToOutputFileURL:[NSURL URLWithString:myUniqueName] recordingDelegate:self];
    }

之后，当我完成录音时

    #pragma mark - AVCaptureFileOutputRecordingDelegate

- (void)captureOutput:(AVCaptureFileOutput *)captureOutput
didStartRecordingToOutputFileAtURL:(NSURL *)fileURL
                   fromConnections:(NSArray *)connections
    {
       _isRecording = YES;
    }

      - (void)captureOutput:(AVCaptureFileOutput *)captureOutput
      didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL
                   fromConnections:(NSArray *)connections error:(NSError *)error
    {//    [self saveRecordedFile:outputFileURL];
_isRecording = NO;

if ([self.delegate respondsToSelector:@selector(didFinishRecordingToOutputFileAtURL:error:)]) {
    [self.delegate didFinishRecordingToOutputFileAtURL:outputFileURL error:error];
}

---

}

你得到答案了吗？还是解决方案？