iphone - AVAudioPlayer with extremely long duration (for ~10 second file)

Question

When playing a file with an AVAudioPlayer (loaded from NSData) I am accessing the 'duration' property as specified by apple's docs like this:

player = [[AVAudioPlayer alloc] initWithData:self.audioData error:&local_error];
NSLog(@"%f",player.duration);

However the duration spits out 268435.199875 for a less than 10 second file.

Any idea what's going on?