Rat like noise at Idle from the engine bay
 

I went out to start my car up after a long standstill and I noticed a rat like noise coming from the engine bay.
It only seems to be there at idle and it's not consistent. It makes the noise at non-rhythmical pattern.

I tried to catch the noise on my phone cam but it's hard to notice due to other mechanical noises.

Does anybody have any idea what it could be?

(it was 3degree Celsius outside, my car has been parked for a week)

and no. there wasn't a rat living in there.

Did you try pushing in the clutch to see if it goes away?

I will give that a try.
It sounds like it's associated with some sort of rotating mass though.. not too sure.

It's probably a belt.

+1 to the belt

Is it like a squeaky sound? If so, I'd say belt as well.

yeah. It's squeaky.. It's not consistent though. I figured it's belt as well but it concerned me because it's got a non-rhythmic pattern.

I'll have it checked out when snow clears... winter sucks.