Top of the Pops executive producer Andi Peters is leaving the music show after its move to a Sunday slot on BBC Two.
Andi Peters began his career as a TV presenter
The former children's TV presenter is going back in front of the camera to host BBC One's City Hospital.
A BBC spokeswoman denied he was leaving because of the move to BBC Two and declining ratings, saying he simply wanted to be back on screen.
Top of the Pops' audience of about 1.1 million a week was "really good" for the timeslot, she added.
Peters took over Top of the Pops two years ago and revamped it with a new look, logo and presenters.
He said he wanted to bring the "must see" factor back by making it an exciting event again.
But its ratings remained around the three million mark - less than half the total it was attracting in the mid-1990s.
And after more than 40 years on BBC One, it was moved to Sundays on BBC Two in July.
The BBC spokeswoman said Peters had been considering the move back to presenting "for some time" but wanted to oversee the transfer to BBC Two first.
"The show is performing solidly each week in its BBC Two slot so this isn't the end of the show or time for another re-launch," she said.
"BBC Two is committed to evolving the TOTP brand to broaden the appeal to older and younger viewers - it's an important part of its music portfolio.
"It really is just the case that Andi fancies returning to screen having spent most of his recent years behind the scenes."
Peters said it was "really good" to be going back to presenting television.
"After seven years of making telly, it's great to get to return to the box and even more exciting to be joining a live show, City Hospital," he said.
BBC entertainment head Wayne Garvie described Peters as a "brilliant creative leader" of Top of the Pops.
"The programme and all of us will miss him, but he's a born presenter and it's in his blood," he said.