They're playing the remake/rehash of D.W. having trouble getting rid of her hiccups.
And you're right. Not only that, but the other day, they were supposed to play "What Scared Sue Ellen?", and yesterday they were supposedly to play "Fernkenstein's Monster" (though for some reason, both days my PBS has played Wild Kratts instead).
EDIT: Okay, I looked at the Wiki and saw that this hiccup episode is Halloween-related, so that makes sense... still, I would have prefered "The Fright Stuff", like they usually do.