BBC 1 show The Voice went over budget by £650,000.
The talent show exceeded its budget of £22 million after splashing out on an expensive set and the judges' red swivel chairs, but the BBC is refusing to pay the excess cost and says production company Wall To Wall will have come up with the cash instead.
A BBC insider said: "We handed over a certain amount of money for the show and it is up to the production company how they spend it."
The programme - which featured Jessie J, will.i.am, Sir Tom Jones and Danny O'Donoghue as judges - looks likely to be commissioned for a second series despite dwindling ratings, but insiders claim the costly set was seen as an investment.
A Wall To Wall spokesperson said: 'The Voice UK was the most successful new entertainment series launch on BBC One in a decade. As with any first series, it is important to get as much investment on screen as possible."
Meanwhile, a further £5 million will be invested in the programme in order to boost ratings by giving the show "a few tweaks".
A source told the Daily Star: "The Voice will definitely be back next year. The Beeb reckons it will be a bigger hit with a few tweaks."
There is no confirmation as yet about which judges will be returning, but Eurythmics star Annie Lennox is being tipped to replace Black Eyed Peas rapper will.i.am after he hinted he may not be back on the programme.
A spokesman for The Voice said: "We are more than happy with our coaches and are in talks with them now to be a part of the second series."
This comes after news that the live UK tour featuring finalists Leanne Mitchell, Bo Bruce, Vince Kidd, Becky Hill, Max Milner, Jaz Ellington, Tyler James and Ruth Brown has failed to sell out a single venue.
