Bad cell phone reception.
Sharon : Hello?
George : Hi Sharon it's George again. What time do you think you'll get to the party tonight?
Sharon : Sorry, what did you say?
George : Hello, can you hear me? I said what time do you think you'll be getting to the party?
Sharon : Sorry, I can't hear you.
George : Can you hear me now?
Sharon : No, not very clearly. It's really noisy here.
George : It might be my cell phone, I don't think I have very good reception.
Sharon : Oh, that's OK.
George : Can I call you right back?
Sharon : OK.