Girl band Miss Frank were eliminated from the competition yesterday after finding themselves in the bottom two with hotly-tipped singer Danyl Johnson. Simon Cowell immediately described Johnson's setback as "a joke".
According to The Sun, show chiefs are now keen to ensure that "the best acts" do not end up in the sing-off again.
A source said: "They need to work out whether they've given the acts the best songs."
Cowell's protégé Johnson was also said to have been surprised by his narrow escape, though he later told The Xtra Factor that he had expected to do badly.
The insider added: "He looked like a broken man when he came off stage - absolutely destroyed. He was stunned to be in the bottom two, he thought he was the best thing on the show."
The X Factor continues on Saturday at 8pm on ITV1.