.caf file length differ ,even duration is same
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I have .wav sound file for duration 5sec with Audio channel 2 and total bit rate is 1411200. I am converting this file to .caf format via command on terminal.
After file conversion it give following info audio duration is again same ( 5 sec), but audio channel is 1 and total bit rate with 705600.

Now this .caf file is keeps inside NSBundle. I need to recording same duration audio file and compare it with pre-recorded file. But when ever i NSlog both(recorded and pre-recorded) sound with NSData length ,it gives large byte difference(approx. just double).

I do not understand why this happen ,even both sound is .caf file with same duration.
Please help me. Thanks in adv.

Thanks 
Sudesh