When you work at two radio stations in one day, as I did sometimes in the early '90s, you might start to say the wrong call letters on the air.
As far as I know, I only did this once. During an air check critique session at KBIA, the program director heard a break in which I said, "We now return to the Cleveland Symphony Orchestra on KC...on KBIA."
Fortunately, the p.d. took this with good humor.
"You're entitled to one of those," he told me. "During our last pledge drive, I accidentally started to say W..., which was the start of the (call letters) of another station where I'd worked."
It's refreshing when a program director accepts that we're all human.