We've had similar things happen here. Husband is very tech-savvy so I'm sure we're pretty much locked-down. Our phones are "call and text" only - I'd have to manually link my phone up to our network (and I don't).

Anyway. We were watching a video on YouTube with a Japanese girl playing one of Japan's stringed instruments (can't recall the name). I said something about her style reminding me of Harpo Marx playing the harp. When we refreshed the YouTube page, there were two videos suggested with Harpo in them.

Something in here is listening but we don't know what.