The suit said the employees were Piolin's friends, one from high school, who profited from his success on radio and wanted revenge for being fired.
Sotelo's long-running show, "Piolin por la Manana," was abruptly cancelled by Univision without explanation last month. It was subsequently reported that a lawyer for a former staffer had written a letter to Univision in April seeking settlement of sexual harassment allegations.
Sotelo's lawsuit details an alleged offer by the employees through their lawyers to "seal their lips" and take their allegations "to their graves" if Sotelo paid them.
Attorney Richard R. Clayton, named as a defendant, did not return a call for comment.
It said the friends hired by Sotelo, one who was working at a fast food restaurant after declaring bankruptcy, were given an opportunity to break into radio. The six defendants include a bakery deliveryman, an online copywriter, a medical waste hauler, a warehouse employee and a female traffic reporter.
Some were trained in radio techniques, the suit said, and one man was given a simple job of bleeping out curse words from the freewheeling show before they reached the air. It said that man sometimes failed to stop the words from getting on the air and was written up for it. But Piolin said he interceded to keep the man's job.
The suit painted a picture of a show troubled by jealousy and questionable activities by employees.
It said trouble started when a Piolin friend who was named manager of the show found out how much money Piolin was making on promotional ventures and demanded a raise up to $1 million. It said the same man used his position to get jobs for friends, relatives and a young woman with whom he started an extra-marital affair. This, the suit said, "created a workplace drama when (his wife) drove to Univision Studios and demanded the woman be fired."
The suit said the woman, who had been given a late-night talk show, was discovered giving away prizes to her family members and ultimately was fired.
"Piolin is appalled by the conduct of his former colleagues and personal friends," the lawsuit said.
His attorney, Jeffrey Spitz, called the alleged extortion scheme "one of the most brazen, shameless and despicable examples of a shakedown that I have ever seen."
Sotelo, who was recently elected to the National Radio Hall of Fame, played corny jokes and pranks on his morning drive time show but also hosted politicians including President Barack Obama to discuss issues such as immigration reform.
In 2007, he travelled to Washington, D.C., to present lawmakers with 1 million letters in support of immigration reform. He often spoke on his program of his own experiences as an immigrant crossing the border illegally as a teenager and later obtaining papers and becoming an American citizen.
Piolin, whose nickname means "Tweety Bird," also voiced roles in "Beverly Hills Chihuahua" and other movies. He recently signed a contract with SiriusXM satellite radio.