Getting audio file properties (length and size)

Question

Hi,
when I load a screen I have two labels. One should display me the audio file length (in seconds) and the other the size (in MB).
But I cant get it to work. The labels just show me '(null)' all the time.
What am I missing here?
@interface AudioViewController : UIViewController {
NSString *size;
NSString *length;
IBOutlet UILabel *audioSize;
IBOutlet UILabel *audioLength;
-(UInt32)audioFileSize: (AudioFileID)fileDescriptor
//Get file size
UInt64 outDataSize = 0;
UInt32 thePropSize = sizeof(UInt64);
OSStatus result = AudioFileGetProperty(fileDescriptor, kAudioFilePropertyAudioDataByteCount, &thePropSize, &outDataSize);
if(result != 0) NSLog(@"cannot find file size");
NSLog(@"file size: %@", result);
return (UInt32)outDataSize;
//Get file length
NSTimeInterval seconds;
UInt32 propertySize = sizeof(seconds);
OSStatus err = AudioFileGetProperty(fileDescriptor, kAudioFilePropertyEstimatedDuration, &propertySize, &seconds);
if(err != 0) NSLog(@"cannot find file length");
NSLog(@"file length: %f", seconds);
size = [NSString stringWithFormat:@"%i", outDataSize];
length = [NSString stringWithFormat:@"%f", seconds];
- (void)viewWillAppear: (BOOL)animated {
audioSize.text = [NSString stringWithFormat: @"%@", size];
audioLength.text = [NSString stringWithFormat: @"%@", length];
Thanks for your help!

Answer 1

you should not attach sounds to timelines if you want precise control of your sounds, and use actionscript. 
that said, your sound will play if you assign its sync property to event, instead of stream.