Garageband songs exporting to Itunes with missing audio

So the problem I've been having is with Garageband songs exporting into iTunes. Occasionally, a track will be bounced and when I start playing it back in iTunes the audio completely drops out for a few seconds, while the track appears to continue playing, with time still advancing on the playbar. This doesn't happen every time, but seems to occur more often with songs with a large number of instrument tracks.

I had a similar issue with songs purchased from iTunes, in which the song would stop playing for a few seconds. An update to the latest version of iTunes as well as upgrading to Yosemite seemed to solve this issue for my purchased songs, as well as most of my exported songs from Garageband. Today, I have attempted three different exports of the same song, all at different quality, and have had the same result. There does not seem to be any rhyme or reason to when the audio will cut out during playback. It occurs at different points in the song each time I export.

This has only been an issue with Garageband 10 (I won't go into the myriad issues I have with the application itself, although, yeesh) and I am using an older MacBook Pro with a recently installed 200 GB Solid State Hard Drive. I haven't seen any other forum posts about this problem, so I'm wondering if it's a RAM issue with my older model, a soundcard issue. or simply some kind of glitch with garageband.