Her: Can I have your name please?
Me: Elspeth Duncan
Her (pause): Can you spell that?
Me: E-l-s-p-e-t-h ...
Her: T-e ... I didn't hear you after the T.
Me: Not T. E ... l-s-p-e-t-h ...
Me: No. Elspeth!
Her (meekly, maybe because she hears irritation in my voice): Miss Duncan, can you start over please?
Me (slowly): E-l-s-p-e-t-h Duncan (not spelling Duncan although I've experienced a few people who also can't spell Duncan)
Her: Okay, I'll have someone call you back. Can I have your number?