I'm not sure that this qualifies as a mondegreen, but -

The CTV Drama channel has a blue screen with a warning before many CSI type shows. If you don't read the screen, but just listen to the woman's voice reading the warning, it sounds like she's saying, "This program contains violence, coarse language, amateur subject matter."
If you read the screen, it says, "This program contains violence, coarse language, and mature subject matter."