When Cute Goes Terribly Wrong

Dexter has been doing his pterodactyl thing for weeks now. He screams if he's happy, he screams if he's sad. He just screams and screams and screams. He used to have a small warm-up period to the impressively loud piercing tones that emanate from his little lungs. Now he'll just be sitting quietly and shriek like a banshee. He's scared many people by nearly breaking glass with his screech when it came out of the baby blue. I'm not sure what to do. He doesn't understand that he's wearing on our nerves at times. He doesn't understand the word "no". He doesn't even speak English yet. I hope it's a phase, but weeks have gone by now. His vocabulary consist of loud and louder. I can't believe we made one without a mute button or volume knob.