That's what puzzles me. She heard his voice again over the phone at eleven fifteen. And I heard it ten minutes later! But that could be explained
9 seconds sound clip from the The Adventures of Superman - The Mystery of The Walking Dead classic radio series.
You can hear this line at 00:18:01 in the radio play.
Quote context
[...]
- Why are you making a point of that, Kent?
- Miss Lane and I left here last night at ten fifteen.
- And the words he spoke were the same words he screamed at her from his cell.
- But that's impossible. At ten twenty-five he was in his cell - either dead or alive.
- How? Since when do dead men talk over the telephone?
- Well, assuming he wasn't dead - that he was in a - a cataleptic trance...
- Oh, no.
- I'm sorry he's not on duty now so he could tell it to you himself.
[...]