Actually, I am sitting here wondering why I can hear my youngest son making noise through the baby monitor when there is no one home but me. I turned the TV on mute because I thought I was hearing something in the background. My ear is all plugged up so sound is distorted anyway. I heard it after I muted the TV. The only other thing it could be is my cat, but she is in the basement. It might be that the monitor is crossed with another family's monitor. But is really sounds like my son.

Ugh.

ETA: I only heard one small noise. I made it sound like it is ongoing. It was probably my cat.