Definitely. There is a freeware program called Audacity you can get from download.com. It gives you precise control over sound files at the millisecond level. Open you sound file and place your cursor at the start of the sound wave. Select "Insert Silence" from the "Edit" menu. Enter the SOA, e.g., ".241" for a 241ms SOA (note the decimal!!). Save the file, and that's it. Audacity will let you zoom in to see the sound amplitude at any given ms. This is a nice way to confirm that the audible sound is starting at the appropriate moment. That's it. Let me know if you have any trouble with it!