Do as the wife did once...
She took a call from someone similar to your caller, after hearing the opening gambit she said.
'ooh, hang on a sec, someone's at the door'....and remained sat there,watching TV with the phone laid beside her, and the caller waiting.
After a few minutes, she picked up the phone carefully and listened....the guy was talking to a colleague...
'i don't think she's hung up, i'm not sure'
Colleague..'hang on, i'll ring the number...no, it's engaged, so she must still be on the line'
'There's no-one there, hello, hello madam ?'
The wife sat there, sniggering.
They gave up iafter a short while...