The exact source behind the PBTV cackle is not widely documented, which has left listeners to describe it by how it sounds rather than where it came from, with one popular nickname calling it a submarine noise. That ambiguity has not stopped it circulating as a short reaction clip, where its brief length and instantly odd laugh make it easy to drop into memes, edits, and chat replies. Because it works without context or dialogue, creators keep returning to it for mocking moments, and its distinctive cackle helps it stand out among more generic laughter sounds.