Hello! I've recently purchased a 3-4 week old male guinea pig as a companion for my slightly older male. Since I've gothen him, I've noticed that he sometimes makes clacking noises at me when I take him out of his cage I've heard crackling noises being associated with URI, but he doesn't have any other symptoms (i.e., sneezing, anorexia, runny eyes, lethargy, etc.) and the noise really seems to be directed at me, as I've never heard him make it while he's in his cage. Still makes me pretty nervous though