Voices on indoor camera videos that are not in my household?

I have caught voices of people talking on a video. I was having a conversation with a friend and when I played back the video, I could hear a guy talking for a minute or so. It was over while my friend and I were talking. On another one, I was making coffee in my kitchen on a sunday am by myself at home. When I saw the video I heard someone cough. is this typical that youd hear thru walls and other people's voices? I didnt hear this while it was happening. Found it when I was listening to the videos saved. Only these 2 times have I caught it happening and I have had this indoor ring camera since august of 2020. These 2x happened in January 2021. Curious.