I've been meaning to post this one for a long time, but couldn't find a copy that I could use an embedding code for, until I found this print.
Anyway, there is one flaw in this short story. I'm sure you'll see it as we go along. Casey Kasem (Robin) has a dual role in this one, as he also voices one of the teens. Come to think of it, that couldn't have been too hard. They could've asked him to use his Shaggy voice from Scooby-Doo.
Here's "Haunted House":
Edit, 7/26/18: Dailymotion deleted the video. Soon as we find another copy, we'll bring it back.