Timmy Mallett did not sing the vocals on his famous hit Itsy Bitsy Teeny Weeny Yellow Polka Dot Bikini, it has been claimed.
Teacher Everton Barnes, 45, told The Sun that he sang the lead vocal on the No 1, because Timmy could not hit the notes.
The former Wacaday presenter, 53, topped the charts for three weeks with the song in 1990.
Everton was an RnB vocalist at the time, and was drafted in by producers Nigel Wright and Les McCutcheon to replace Timmy.
He said: "The producers decided Timmy was the perfect bloke to do the vocals as he was all the rage.
"But when they got him into the studio they realised his voice was as flat as a punctured pancake.
"There was no way that the record company could release it as it was."
"I sang the whole vocal track and Timmy's was shunted into the background.
"I didn't want anybody knowing as it was a bit embarrassing and I still had ambitions in the music business."
Everton made less than £5,000 in royalties and is upset that Timmy has been singing the song on I'm A Celeb.
He said: "I've decided to speak out as I feel it's a great shame Timmy is going around singing the song when he knows it's not his voice on it.
"It was even my idea to insert the 'Oh yeahs' and now Timmy is going around shouting 'Oh yeah' in the jungle as if it was all down to him."