1.First, say 'sorry' and gently pass it first you don't understand.
- Remorseful?
- Remorseful, but I can not hear clearly.
- I don't (quite) have it.
- Sorry, I had been a little confused.
- Excuse me, I don't determine what you said currently.
2. Question to talk again. Or explain more.
- Can you speak again?
- Could you speak slowly?
- Can you explain me again?