The shows with the constant sound effects also usually have what seems like a relatively new format: they try to make it sound like the hosts (it's always two hosts) are a couple of friends, interested laymen, having a talk at their house about the topic. So they stop to interject ("right?!" "No!"), they talk over each other but only occasionally so as not to annoy the listener, they basically feel like your two friends who've read the same Wikipedia page and are discussing it at a party.

And it's during this "conversation" that they play the sound clips:

HOST 1: "So there's this interesting thing they've just discovered, Host 2"

HOST 2: "What's that?"

HOST 1: "Scientists have discovered that when you eat..."

chomping and chewing noises

HOST 1: "... you're actually oppressing black people."

prison cell door slams

HOST 2: "What, seriously?"