Just last week Sinead slated the show in one of several open letters to Miley Cyrus.
During the ongoing spat with Miley, in which Sinead has criticised the former 'Hannah Montana' star's recent behaviour, the 'Nothing Compares 2 U' singer turned her anger onto talent shows.
“I feel sorry for the murder of music and rock 'n' roll, which has happened because of the industry," she wrote.
"Because of Simon Cowell, Louis Walsh. They've murdered music. I stand to say it on behalf of every musician in the world and they'll agree with me.”
Simon – who celebrated his 54th birthday this week – reacted on Twitter with a joke post writing: “I think sinead o'connor would be a real fun guest judge on X factor. She loves the show and everything I do. Let me know sinead.[sic]”
Despite her recent outburst, a stint on the show wouldn’t be too shocking after Sinead revealed in 2009 that she would have auditioned for the ‘X Factor’ if she was starting out in the music industry today.
But it was a different story two years ago when she said she wouldn't allow her daughter, who also wants to be a singer, to apply for the show.
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