The Elder Scrolls IV: Oblivion

Audio problem: Several of the NPCs use multiple voices depending on when you speak to them, sometimes their voices will change completely during a single conversation.

Trivia: While it's obvious that there are no children in the game, for controversy reasons, there are actually 2 child skeletons that were left in the game. They are seen when you complete the Dark Brotherhood's quests, by the skeleton of the night mother.