Irish Rail has admitted there are teething problems with its new every-ten minute DART service.
It cancelled two services and cut another short yesterday evening, as its higher frequency timetable beds in.
Passengers have been complaining of cramped conditions, as the company now runs some shorter carriages.
Irish Rail's Jane Creegan says they hope to iron out the issues in the next few days.
"We have had some teething problems I think it's fair to say, particularly around capacity with our more frequent services".
She promised that the company, along with the National Transport Authority will review the new timetable to "ensure we do have enough room for all the passengers who wish to travel with us".