Random Voice Heard From AirPods

Hello,

I was on a FaceTime this evening using my AirPods when a 'glitch-like' sound began and a voice started speaking saying, "Hi, [my name]. Sorry", and after about 30 seconds followed by the same 'glitching' sounds. Is it possible for someone to connect to AirPods and speak through them? Is this a problem with my iPhone? This voice was one I did not recognise whatsoever and the person on the receiving end of the FaceTime said they did not hear a thing. Please let me know if anyone has experienced a similar thing or what may be the reason behind this. Thanks!