Is my guinea pig sick if he is making low noises?

Guinea pigs make a variety of sounds to communicate with each other and their human owners. Some common sounds include wheeking, chattering, purring, and rumbling. Low noises, such as a soft chirping or clicking sound, can be a sign of contentment or happiness. However, if your guinea pig is making low noises that are unusual or accompanied by other symptoms, such as lethargy, weight loss, or changes in appetite, it is important to take them to a veterinarian to rule out any underlying health problems.