Fame Academy producers have admitted there is a genuine rift between "tutor" Richard Park and host Patrick Kielty.
Fame Academy is now down to the last four contestants
In a radio interview Park accused Kielty of being "desperate" to side with contestants in the BBC One reality talent show.
He denied that their on-air spats were staged to boost ratings, and said he had often become "irritated" with Kielty for talking across him.
A show spokeswoman confirmed that the two men were not on speaking terms.
She added that their dressing rooms had been moved apart.
Park, the show's "headmaster", said he had not socialised with the BBC show presenter away from the studios.
"I would be delighted to see him," he told Simon Mayo's show on BBC Radio Five Live on Wednesday. "I am not trying to be insular or chauvinistic.
"The critique I am giving is not being digested by the audience because somebody is talking through me halfway through."
Critics of the show accuse it of playing up the Kielty-Park conflicts to try to boost its viewing figures against rival Pop Idol.
But Park appeared to be genuinely upset that his views had not been given adequate airtime because of what he said were Kielty's constant interruptions.
Asked by Mayo whether their fall-outs were "for real", he replied: "It is unfortunate we haven't built any sort of relationship, and the irritations have outweighed the pleasantries.
"I do not feel we are moving the programme along fast enough."
He added: "Patrick Kielty is there to host the show, but he is too desperate to voice an opinion, too desperate to side with the artist, too desperate to side with the people in the audience."
He said it was "unfortunate" their rows had been broadcast, and urged Kielty to respect his criticisms of the students.
"I haven't just wandered in off the street. I have been in the business for many years and I think I have got a reasonable ear."
Park made his name in radio, as the programme controller at London pop station Capital FM. He is now a consultant for easy-listening station Magic.
The pair fell out again on Saturday when Park criticised student James Fox's rendition of John Lennon's Woman as "absolutely appalling".
"That may have been many things but it wasn't absolutely appalling," Kielty countered.
A Fame Academy spokeswoman said there was a "genuine personality clash" between the two.
She said: "Anyone who watches it can see it isn't stunted. You can see the anger on Richard's face.
"We've had to move their dressing rooms apart. It's quite a lot of trouble to go to for a publicity stunt."