Rattling Noise from AC?

Well, I decided to use the AC on my 2003 Focus ZX-5 (2.0 and auto) and I'm hearing this weird sort of rattling noise. The ac works fine and all, but I'm perplexed at the odd noise it's making. I don't use the AC often since
I drive with the windows down most of the time. Does my lack of using the ac have anything to do with it? If there's a problem, it's under warranty, but I'd just like to see if I could figure it out. Thanks.
Mojo
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My brother said when he bought his Focus, that the garage said to run the AC for at least an hour a week to keep it in good working order.
Don't know if there is any truth in doing that though?

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Hey.
If you regularly park your car outside it could just be something simple like a leaf blowing around in the duct work. My old car regularly spit leaves at me throughout the winter because I parked it outside under some trees.
Erin

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Ooo, sounds like a good idea. I park my car outside and surprise surprise, it's under a tree. I'll investigate it tomorrow. Thanks. :-)
Mojo

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