Alex Carey's controversial reprieve on the first day of the third Ashes Test was down to an error by the operator of the Snicko technology. Carey admitted he edged a delivery from England pace bowler Josh Tongue that was caught by Jamie Smith when the Australia wicketkeeper had 72. Carey went on to make 106 in Australia's 326-8 at the Adelaide Oval.

BBG Sports, the company that owns Snicko, has accepted culpability for the mistake. "Given that Alex Carey admitted he had hit the ball in question, the only conclusion that can be drawn from this, is that the Snicko operator at the time must have selected the incorrect stump mic for audio processing," BBG told BBC Sport. "In light of this, BBG Sports takes full responsibility for the error."

It is understood the sound used for the review was taken from the stump microphone at the bowlers' end, rather than the strikers' end. This caused a discrepancy between the pictures and sound wave shown to TV umpire Chris Gaffaney. BBG Sports have confirmed it will investigate the error and take steps to ensure it will not be repeated.

The decision review system (DRS) technology, which is mandatory in matches played in the World Test Championship, is provided by the host TV broadcaster of the home team. In this instance, the host broadcaster is Fox, which uses BBG to provide Snicko. Fox has opted not to comment.

Australia were 245-6 in the 63rd over of the day when Carey aimed a cut at Tongue, which end in the gloves of Smith. On-field umpire Ahsan Raza rejected the appeal of England, who immediately reviewed. Despite a large spike of sound on the Snicko technology, Gaffaney struck down England's review because the ball appeared to be away from the bat when the sound occurred. That discrepancy arose from the sound being taken from the non-striker's microphone.

"I thought there was a feather or some sort of noise when it passed the bat," said Carey. "If I was given out I think I would have reviewed it, probably not confidently. It was a nice sound as it passed the bat."

England have raised the matter with match referee Jeff Crowe. "I don't think we've done anything about it so far but after today, maybe that might go a bit further," said England bowling consultant David Saker. "There have been concerns about it for the whole series. We shouldn't be talking about this after a day's play, it should just be better than that. It is what it is."

There has been debate about 'Snicko', the technology used in such situations in Australia, throughout the series after a number of inconclusive incidents. In the first Test in Perth, England wicketkeeper Smith was given out caught behind on review despite a spike coming after the ball had passed his bat and glove. That was explained as being because the technology used in Australia has a two-frame gap between the pictures and the sound wave.

Carey is not new to Ashes controversy. He was the wicketkeeper who famously stumped Jonny Bairstow at Lord's in the 2023 series, resulting in a febrile final day. On his reprieve he added: "Snicko obviously didn't line up. It is just the way cricket goes - sometimes you have a bit of luck. Maybe it went my way."

Carey was also asked if he is a 'walker' - the tradition where some batters leave the field without waiting for a decision if they believe they have hit the ball. He joked "clearly not" in response.

Cricket has always been forward thinking with the use of technology. TV replays were used to adjudicate line decisions more than 30 years ago. What is now known as DRS was first used in 2008, albeit with some teething problems. In 2009, a report by the BBC said the system was in "crisis". Gradually, DRS has become part of the fabric and drama of the game, used not only in international cricket but many domestic T20 leagues. Major controversies are few and far between, however discrepancies can arise from country to country, depending on which technology provider is used. In this instance, the Snicko system used in Australia differs from the Ultraedge operated in the UK.

Australia were 245-6 when Carey attempted a cut to Tongue. England appealed confidently, thinking they had heard an edge, but umpire Ahsan Raza was unmoved. After captain Ben Stokes challenged the decision, the footage reviewed by TV umpire Chris Gaffaney showed a spike but this came before the ball had reached the bat. Gaffaney also said he believed there was a gap between bat and ball. As a result, Carey was given not out.

The technology is the responsibility of the host broadcaster, which is Fox Sports in Australia. Fox take Snicko from a company called BBG Sports. "I am concerned about the Snicko," said BBC Test Match Special commentator Jonathan Agnew. "We have had a number of incidents where the Snicko has not been good enough. I did talk to match referee Ranjan Madugalle in Brisbane and he said we are really concerned about Snicko in the series. It was a proper spike and appeared this time before the bat. It couldn't have been anything else. The software isn't working right. Carey should have been out caught behind."