It takes the fun of a Rick Roll and applies it to the phone. You take your knowledge of what current, horrible pop song your friends or acquaintances hate. When the song comes on the radio, you call them with the volume of the song really high. When they answer the phone, thinking they are getting a call from you, they are instead greeted by the horrible song. Bam! They've been "audio rick rolled!"
Me: Owl City - "Fireflies", or Kesha - "Tik Tok" comes on the radio. I turn it up really loud and dial my friend.
Friend: (Answers phone) Hello?
Me: (Crappy song playing really loudly! I let it go for a little bit and then hang up.)
Plus, it works even if they let it go to voicemail.
Then I text them: You've just been "audio Rick rolled"
Other potential songs:
Sisqo - Thong Song
Fergie - My Humps
Hanson - Mmmbop
Baha Men - Who Let the Dogs Out?