I once said to the telemarketer that she has a sexy voice, and that I can imagine her in the office outfit with a tight skirt, and some business makeup, potentially wearing glasses, question hers relationship with her boss etc. She hung up after 2 mins :D
It was one of the options on the list but being a woman myself I find that more creepy than funny.
Heavy breathing was also on the list... honestly phone calls freak me out to begin with. If I had to answer a call or even make one and the person is only breathing... Id be out so fast. Many horror movies start that way. I'm good with not dying