I called one show ONCE.
The Rusty Humphries show.
They do play the show on the phone for you while you wait, but Lord! Then you have to meet the call screeners criteria!
LOL
It is easier to comment here.
I called Chris Plante (WMAL) a few months ago, and was on-hold when call screener said I was next-up, after >10mins, but I had to drop-off, as UPS was at door w/ ORM-D delivery, which required signature. They had a 10-15sec delay between streaming and phone. That was my only radio show call.