In case anyone finds their way to this thread and is worrying that something is terribly wrong with their chicken, I thought I would post a follow up. This may not always be the case, but our chicken that was making a noise just like the one in the video turned out just fine. I'm guessing it was either the weather (hot then damp and cold) or she got something stuck in there. Either way, she went to bed and was fine by the next day. Chickens are strange, but wonderful creatures!