Dell 3300MP Issue

My projector was in use a couple weeks ago when a loud surge and pop sound occured. I immediatly turned it off and let it sit for a while. I thought it might have been the lamp, however when I turn it on, I get the image just fine except there is a loud like humming noise that comes from the main case that vibrates the image so it is unreadable. The noise is extremly loud and almost sounds like a fan is not working correctly. Does anybody have any ideas?

update : I took apart the case and have found the source of the noise, however I have no clue what it is. It is the spinning disc looking thing thats directly in front of the lamp. A small chip of it has broken off and I found it laying in the case. Anybody have any idea what it is and how to fix it?

Thanks