The BBC today apologised for keeping £106,000 made from premium-rate phone calls on about two dozen shows that should have been given to charity.

In the latest scandal to hit the television industry over phone-ins, the BBC also admitted that viewers of Making Your Mind Up, the BBC1 show that chose last year's UK entry for the Eurovision song contest, Scooch, were misled into voting before phone lines had opened. In that case, the BBC made £6,000 from ineligible calls that has also gone to charity.

The BBC Trust chairman, Sir Michael Lyons, today said that the money had now been repaid to charity, including interest totalling £123,000.

The trust has also ordered the BBC to make an onscreen apology – the first time the corporation's governance and regulatory body has imposed such a sanction.

Lyons said the issue involved the BBC Worldwide subsidiary Audiocall, which provides premium-rate phone lines to many BBC shows.

He added that about two dozen shows had been affected between October 2005 and September 2007, although he refused to name them.

Lyons said new technology had since been introduced which meant the problem had been resolved.

The trust has asked the BBC director general, Mark Thompson, to look at disciplining a "handful" of staff.

Lyons made it clear that senior staff within BBC Worldwide and the corporation did not know about the problem and nor did staff who worked on the affected programmes.

He added that he did not know why staff at Audiocall did not report the issue.

Lyons said: "There is no legal impropriety but it is a failure in the behaviour of these staff and the BBC's own systems.

"It was a matter of serious misjudgment by a small number of people and a serious failing in how the BBC controls its PRS premium-rate phone services and its relationship with viewers and voters.

"These problems can't continue into the future and there are lessons to be learned and disciplinary action may take place amongst staff."

He added: "There is no room for complacency here. This is an organisation intent on living by the highest standards in the industry."

These latest TV deception revelations follow the record £5.675m fine imposed on ITV (an independent broadcaster in the UK) yesterday by Ofcom over the commercial broadcaster's phone-in scandal.