The Simpsons Christmas Special: Simpsons Roasting on an Open Fire - S1-E1
Audio problem: When Homer is putting Christmas lights around the outside of the house, he falls from the roof. You can then hear Lisa and Bart sarcastically clap. But you can see they both have their hands by their side, and no-one is clapping. (00:04:55)
The Simpsons Christmas Special: Simpsons Roasting on an Open Fire - S1-E1
Audio problem: When Lisa and Maggie are touching Bart's surgically removed tattoo, he says "Ow", but look at the way he says it. His mouth moves when he says "O" but doesn't move when he says "w". (00:07:50)
Audio problem: Just after Mr Smithers says "...so that we have the energy to from your favourite video game to yummy cotton candy machines", all the children start clapping but the sound of clapping starts BEFORE they start clapping. (00:05:05)
There's No Disgrace Like Home - S1-E4
Audio problem: When Marge gets drunk at the picnic, she falls on Homer while saying "Homie, did you try the punch?", her lips don't move. (00:06:20)
Audio problem: When Grandpa Simpson is typewriting a letter in his room, the words he's spelling out loud don't match his fingers hitting the keys.
Audio problem: When Jimbo says "Yeah come on Bart" his mouth doesn't move to start with and then makes weird motions rather than mouthing words. (00:09:45)
Audio problem: When Lenny introduces Princess Kashmir, his mouth is open without moving when he says "presenting", and when he says "Princess Kashmir", his mouth only moves when he says "Princess", but is closed when he says "Kashmir." (00:07:50)
Audio problem: When princess Kashmere is introduced, we hear Homer laughing, however we see him eating and not opening his mouth. (00:08:00)
Audio problem: During the party, when Princess Kashmir asks Homer to dance, her mouth doesn't move. (00:08:10)
Audio problem: Both Lenny and Carl's voices are wrong. At one point Carl's voice is higher pitched, and Lenny keeps speaking like Moe, or like a voice we haven't heard before.
Answer: I'm not sure if this is the one you're thinking of, but an episode of "Ray Bradbury Theatre," called "A Sound of Thunder," dealt with a similar matter: a group of hunters travel back in time to hunt dinosaurs, only to find things have changed when they get back because someone stepped on a butterfly.
Xofer