I've had chirpers; only female. I have a video of one chirping but it was when I had guinea pig cages so I don't know if I can upload it. It sounded like a bird chirping. The second one sounded like a singing canary. It was very melodic; like a song. She chirped the first time at night. It was so loud, all of us woke up and couldn't figure out what it was. Once I came downstairs, she stopped. After that first time, she chirped a lot. I always suspected that it was a warning. When she'd chirp, the others would freeze. I could walk right up to her and she would keep chirping. Her mouth would be in sort of an O shape, but her mouth never moved. It looked like the sound was coming from her throat... it would vibrate as she chirped. It was a beautiful sound. I didn't have a videocamera so I never taped her.