Was it this one?
https://www.youtube.com/watch?v=U_BF88VYRvE
The "hello" is bizarre. It's like something a weapon AI from Metal Gear Solid would do to flush out its enemy.
The tune is also weird. It's not a recognizable folk or children's tune, and it sounds vaguely Japanese, like background music from a Sega Pico game.
If I heard an ice cream truck playing this come down my street, I'd think I was in an episode of Black Mirror, or some sort of analog-horror scenario. I'd do my best to find a good hiding place and avoid being seen. (Maybe crouch in a cardboard box?)