*** Terminating app due to uncaught exception 'NSInvalidArgumentException',reason: 'Invalid type in JSON write (NSConcreteData)'

我正在使用此代码..

dict=@{@"access_token":[defaults valueForKey:@"TOKEN"],@"email":email,@"prayer":passData};

if ([NSJSONSerialization isValidJSONObject:dict]) {
        NSLog(@"Proper JSON Object");

    }
    NSError *error;
    NSData *jsonData = [NSJSONSerialization dataWithJSONObject:dict options:NSJSONWritingPrettyPrinted error:&error];

    NSURL *URL = [NSURL URLWithString:url];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL
                                                           cachePolicy:NSURLRequestReloadIgnoringCacheData  timeoutInterval:10];

    [request setHTTPMethod:@"POST"];
    [request setValue: @"application/json" forHTTPHeaderField:@"Content-Type"];
    [request setHTTPBody:jsonData];
 AFHTTPRequestOperation *op = [[AFHTTPRequestOperation alloc] initWithRequest:request];
    op.responseSerializer = [AFJSONResponseSerializer serializerWithReadingOptions:NSJSONReadingAllowFragments];
    [op setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation,id responSEObject) {}

我需要以这种格式发布值

{
    "access_token" = 2cf0d8a66654fa4f;
    email = "";
    prayer =     {
        audio = <63616666 00010000 64657363 00000000 00000020 40e58880 00000000 696d6134 00000000 00000044 00000040 00000002 00000000 6b756b69 00000000 00000000 66726565 0000000>
 98903013 31faae9c bb7b0780 80808080>;
        "category_id" = "";
        description = "";
        "expired_date" = "Expiration Date";
        "is_audio" = 1;
        "is_urgent" = 0;
        "prayer_access_id" = "";
        "prayer_type_id" = 1;
        subject = "";
    };
}

我不知道为什么会发生这种情况,我之前用这种格式发布了值,但是当我尝试将音频作为数据发布时,我得到了这个例外.
提前致谢

编辑

我在这里制作数据

NSData *audioFile=[self audioData];
 if (audioFile==nil) {
        [passData setObject:@"" forKey:@"audio"];
        [passData setObject:@"0" forKey:@"is_audio"];

    }else{

        [passData setObject:audioFile forKey:@"audio"];
        [passData setObject:@"1" forKey:@"is_audio"];
    }


-(NSData *)audioData{
    NSArray *dirPaths = NSSearchPathForDirectoriesInDomains(
                                                            NSDocumentDirectory,NSUserDomainMask,YES);
    NSString *docsDir = [dirPaths objectAtIndex:0];
    NSString *soundFilePath = [docsDir
                               stringByAppendingPathComponent:@"recordTest.caf"];

    NSURL *url = [NSURL fileURLWithPath:soundFilePath];
    NSData *audioData=[NSData dataWithContentsOfURL:url];
    return audioData;
}

这就是我插入音频文件