Dial I for Murder

The home phone rang at 10.00 pm.
I have a few family and friends who will ring around this time, but still that first ring jangles the nerves as I check the clock to confirm the lateness of the hour.
10.00 pm.
The rain was hitting the windows at a 45 degree angle and the dogs raised their heads in query.
10.00 pm.
I answered. 'Hello?'
There was a muffled noise at the other end.
Someone crying? Someone choking?
'Hello?' Louder this time.
Still no response, but someone definitely there.
Usually I would hang up at this point, but something made me persist.
'Hello?'
A quavery voice finally filtered through.
'Hello? Who is this?' The voice was both demanding yet faint.
'Well you rang me.' By now I was getting annoyed. 'It's Karen.'
'Who?'
'Karen. Who is this?'
She told me her name and I laughed.
'Karen who?' She was still confused.
'KT,' I said.
She blamed her new iPhone. Somehow, as she was turning out the bedside light, she'd rung my number.
As I hung up the rain continued to tattoo the window and the dogs returned to sleep.
Now how could I use that in a story...