GEN 2 Engine Noise (Video)

Can anyone help as to what this might be? Is it a belt or pulley?

Loud chirping noise at idle and low speeds. Once the truck is rolling it doesn't seem to come on.
I've tried to check what it is but i cannot figure it out, seems to be stronger in the driver's side but not sure the exact place.

I'm taking her in next week to the dealer but i wanted to see if anyone else had this noise or any indication of the cause.

Appreciate the help.

It could be a loose idler pulley, sounds like something being driven off the belt drive. You could try using a long screwdriver and place it on each driven component and see which one has a vibration. Good luck at the dealer. Let us know.