GarageBand Keeps Adding Extra Seconds

Hi, I'm pretty new to mac, I've had my Mac book for about a month or two. Anyway when I export a song from GarageBand to iTunes and play it there are always a few seconds of no sound at the end of the recording. Now, honestly the couple of seconds aren't a very big deal, but it has been bothering me.
As an example I took this quote from a movie and last couple seconds there is no sound. link (Now I know about copy right laws and I'm just using as an example.)

This is also my first time posting on this forum so if I did something wrong or wasn't clear enough I apologize.

I'd say the problem is you're not putting the end of song marker at the end of the track. If you scroll as far to the right in the track window as you can you'll find a little blue triangle arrow at the top. Drag that back so it lines up with the end of the track you've recorded.

If you're trying to get little soundbytes of movies I don't think this will help though, because I don't think Garageband is meant to handle songs that are only a few seconds long.