Software problems continue to plague the $1.2 billion Opal ticketing system, causing some commuters to appear to be overcharged and the passage of others through crowded stations to be slowed down at busy periods.
At multiple Sydney stations over the past fortnight, large crowds have developed after Opal card readers at the gates malfunctioned. In some instances, they have compelled Sydney Trains staff to throw open the gates for anyone with a paper ticket.
Transport for NSW continues to describe the problems as ''minor'' and a large number of Opal card users seem to be having little trouble.
But issues appear to relate to the display panels that show commuters how much credit they have remaining on their cards. Fairfax Media has seen evidence from multiple train stations this week that many ticket readers are not working properly on a regular basis.
If commuters do not see their balance shown correctly on the reader at the gates after tapping their Opal cards, they may not want to move through the gates and risk attracting a maximum $8.10 fare. This may mean that they have been overcharged. Or they may be unsure what they have been charged, triggering delays as other commuters bank up behind.
Sydney Trains staff have display panels that show them which gates are working well. At one busy CBD station on Thursday, the panels showed most gates had problems.
Images provided by the Rail, Tram and Bus Union demonstrate this is a regular occurrence.
One commuter, Adam Futeran, said he had been overcharged twice this week after tapping off at Central. Mr Futeran said he called the Opal customer service line - who were polite and refunded his money - but he would not have been refunded had he not noticed the overcharging.
A Transport for NSW spokesman said there was no "technical issue" with the Opal causing people to be overcharged.
"The only reason customers will get a default fare is because they have not tapped on or off," he said.
Under the system, a maximum fare is automatically deducted when someone taps on. It could take some time - up to 24 hours - for that fare to be adjusted.