Belt noises

So, I've started hearing this noise at the belts / front of my car, but I dont know exactly what it is. It doesn't happen when the car first starts, it only happens after i've been driving for a while. It sounds intermittent.. Kind of like a squeaky wheel. If the engine is accelerated, it seems to go away, so the sound is only at idle. I took a video of it so you guys can hear it. any help/feedback would be appreciated!

Here's the youtube video of it I uploaded
http://www.youtube.com/watch?v=yDlTUXbX6jg

Open your hood and take another video, you'd give viewers a better idea as to what the problem is