A review of ITV phone-ins has identified a "serious cultural failure" within the company.
Shows including Ant and Dec's Gameshow Marathon and Saturday Night Takeaway were among those involved, an audit of ITV's output has found.
ITV executive chairman Michael Grade described the findings as "horrible" and "inexcusable".
Ant McPartlin said he and co-host Dec Donnelly were "extremely disappointed" their Takeaway show was singled out.
"We'd like to make it clear that we had no idea these problems existed," he continued.
"Ant and I are now reassured that strict measures have been put in place to ensure that these kind of incidents can never happen again," said Donnelly.
Although both he and McPartlin have an executive producer credit on Saturday Night Takeaway, he said they had "no direct involvement in the phone line process".
ITV made £7.8 million from uncounted votes. Mr Grade said the company would reimburse those who were misled - a decision McPartlin said he and Donnelly were "100% behind".
Broadcasting watchdog Ofcom has launched an investigation into the programmes highlighted by the report.
Some 10 million telephone calls were affected by the premium rate errors, and more than eight million callers are now eligible for refunds.
Any money not claimed will be donated to charity.
"I've never been involved in anything as grisly as this or anything that's damaged broadcasting as much as this," Mr Grade said.
Ant and Dec said they had not been aware of the problems
Nobody has been sacked as a result of the findings.
Mr Grade said the motivation of staff involved had been "to get a better show" which was "misguided but not corrupt".
ITV has been accused of "burying bad news" by releasing the Deloitte report's findings on the same day BBC announced programme and staff cuts.
The date of the BBC announcement has been known for several weeks.
But Mr Grade said they had chosen today to release the report because it was the "first available opportunity" since its findings had been finalised.
He said "all energy will go into... restoring public trust".
ITV SHOWS SINGLED OUT
Soapstar Superstar - Production team put wrong contestants up for eviction and over-rode song choices chosen by viewers
Ant and Dec's Saturday Night Takeaway - Contestants supposedly chosen at random were selected on basis of geographical convenience and other factors, including their health and fitness
Ant and Dec's Gameshow Marathon - Winners picked on basis of geographical convenience and whether they would be entertaining on screen, not at random
The X Factor - Some votes cast via red-button voting and SMS text during 2005 final and three episodes of 2006 series arrived too late to be included
Dancing on Ice - Some red-button and text votes received late on one occasion
I'm a Celebrity... - Voting promoted for three and a half minutes on one edition after lines had closed
"It is only by understanding how things went wrong in the past, and being open about them, that we can be sure that we get them right now and in the future," he added.
ITV suspended all premium-rate phone-ins, interactive competitions and votes in March while the auditors conducted their six-month review but phone-ins were later reinstated.
But Mr Grade has now announced the immediate suspension of all SMS and red button voting during live shows.
"We are not satisfied that our providers can guarantee us that their systems are robust. Until we can get absolutely certainty that their systems can deliver what we need them to deliver, the suspension will remain," he said.
Telephone competitions are a substantial source of revenue for commercial TV channels.
Meanwhile, ITV has lifted the temporary ban on new commissions from production company RDF.
The broadcaster halted new shows from the company after RDF accepted blame for a promotional film it made for a BBC documentary about the Queen which was edited out of sequence.