Problem with Keystation 88es pitch bend in GarageBand

Hey everyone! I just had a quick question. I am using a M-Audio Keystation 88es plugged directly into my iMac with GarageBand 6.0.5. I am working on a dubstep song, and so I took a Deep Round Synth Bass, and added a couple effects to give it a very heavy distorted bass sound. When I record the audio, it all sounds just fine. When I push the pitch bend up all the way, the note slides up 4 octaves to give it a wailing sound that sounds great for the song. However when I record it and play it back, it only changes the pitch by a little bit, completely taking away the wails that I heard when recording. Here is a video of the problem to give you a better idea of whats happening. The first is what it sounds like when i just play, and the second is what the recording playback sounds like.

https://www.youtube.com/watch?v=wXHa6goDXM4

😟 Any help would be appreciated. Thanks.

~Alden