telephone manners, or i-got-the-strangest-call-tonight

So I was driving home this evening when my cell phone rings. I carefully get it out of my pocket and answer the phone. The conversation went something like this:

Me: Hello?
Stranger on the other end of the phone: Mphlgh.
Me: Hello?
SOTOEOTP: Eh goap thorkenonen mphlgh.
Me: I'm sorry, you're breaking up.
SOTOEOTP: Uh?
Me, slowly and clearly: You're breaking up.
RUDE SOTOEOTP: F*** you, b****.

So whatever happened to, "I'm terribly sorry, but I think I have misdialed"?