The loud, ear-raping screech before you switch to playing as Laguna in FFVIII. I love the game, but I mute the TV while it's on. I hate it.

On Dynasty Warriors: Gundam 2, when you get game over, Haro (the little spherical mascot of the franchise) pops up, and shouts "FOCUS!". I mean, getting game over is bad enough, but having him pop up and say that, it's like "SHUT UP!".