My jeep is making an awful noise. I'll explain from the start

I went to leave work yesterday and cranked my jeep up. I did not hold the ignition long enough so it did not start. I turned the ignition again and immediately heard an odd popping noise and then a burnt smell. The jeep still did not fire up. I waited for 5 minutes or so and cranked it up again, this time it started. When it started it was making this awful noise.

My problem is I am not sure exactly where it is coming from or why. I am 100% deaf in my right ear and have a hard time identifying locations of sounds (especially when ambient noise is present). It appears that it is coming from the pulley system. For some odd reason the noise is only present at idle. If I am accelerating it goes away.

I am linking to a video so you can hear and an image of the engine bay. Any help would be appreciated.

Image of engine bay
https://drive.google.com/open?id=0B9...UFU&authuser=0

Video: In the video you really have to listen for it. It almost sounds like a cricket from a long way off at night time...(I don't know why that is the description). i can assure you that when you are in/around the jeep, it is very loud.
https://drive.google.com/open?id=0B9...SGc&authuser=0

 

Did it smell like an electrical fire? Your starter might be crapping out. Just a thought.

 

I couldn't hear it in the video. My first reaction was going to be flex plate bolts due to noise disappearing during acceleration. But that would be more of a rhythmic loud banging that would override any normal engine sound.

 

A little update on this one. I took the jeep to O'reillys the other day and had the guy look at it. a vacuum hose had come lose. The guy fixed it in 30 seconds. I will say that 3 years ago I would have felt like a jack *** having him look at it, but being half deaf is a great excuse. In all seriousness though, I was not even close to where the noise was coming from.