"Who you ___ ..." (start of a response to an insult)

• Kind of radio program
• Check for messages, perhaps
• Try to reach a talk radio host
• Touch base via phone
• Type of radio show
• Contact a radio show
• Participate in a radio show
• Format of some talk radio shows

Wikipedia Word definitions in Wikipedia
Callin is a surname. Notable people with the surname include: Arnold Callin (born 1924), Manx politician Grant Callin (born 1941), American writer