The Australian radio and television personality, who is a judge on the show alongside Brian McFadden and Dannii Minogue, caused chaos by calling in sick during filming over the weekend, leaving producers struggling to find a last-minute replacement.
According to the Herald Sun, production was delayed for two hours while Dancing with the Stars judge Todd McKenney was brought in as a temporary judge during Australia's Got Talent auditions yesterday.
Bosses are also thought to have held a meeting to decide if Sandilands still has a future with the series.
Seven Network head of production Brad Lyons said: "Kyle's management advised us that he was too unwell to attend work yesterday. We are monitoring the situation closely."
A spokesperson for Seven added that Sandilands is in "the care of his GP", but other sources have claimed that he is struggling with his ex-wife Tamara Jaber's new relationship with sports star Ken Aseme.
He has caused concern in recent weeks with his weight gain. Friend and colleague Brian McFadden even explained away Sandilands's absence to the Australia's Got Talent audience in Melbourne, apparently joking that he is "so fat he's exploded".
Sandilands reportedly upset radio bosses calling in sick to his breakfast stint last week, with an insider saying: "It hasn't escaped anyone's attention, including advertisers who generally ask for a 'please explain' in these situations. And the worst thing is that Kyle doesn't seem to give a s**t."
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