1999 Land Rover Discovery 2 Squeaky noise when Acceleratin

Whenever I'm at a complete stop and start to accelerate i hear a squeaking noise coming from underneath likes somethings dryed out. It never makes the sound when I'm in neutral or park giving it gas only when i accelerate driving there is also a tiny bit of vibration. I thought it might be the brakes so i change them all out also changed the oil and the transmission still doing it also here is a video link of the sound http://s668.photobucket.com/albums/vv41/hwaire/?action=view¤t=1111111001.flv