Commuters have become so fed up with morning rush hour delays that they burst into a round of applause when a train arrives on time.
Passengers at Stonehaven say services regularly run up to 30 minutes behind schedule and blame problems with the Caledonian Sleeper.
They are especially angry at having to stare through the windows of the overnight carriages at many empty seats they are banned from using.
Now one has gone directly to Transport Minister Humza Yousaf with a demand to get the situation sorted.
But Serco insisted its sleeper was the best-performing long-distance route in the UK, with four in five trains no more than a minute late.
Janine Sydenham, who wrote to the minister, said: “I usually go for the 7.26 or the 7.37 from Stonehaven. The sleeper is due in at 7.15am, but if this is late the other two trains are also late as we have been told there has to be a ten minute gap in between each train.
“Last week it was delayed on Monday, Tuesday and Wednesday and on Thursday we actually gave ours a round of applause for being on time.”
Mrs Sydenham said trains are also being overcrowded due to the knock-on delays.
“What makes it even more frustrating is that when the sleeper comes in and lets passengers off in Stonehaven, we can see whole carriages of empty seats, but we are not allowed to get on board to use them.”
Fellow commuter Christine Steel said it had “gotten to the point where missing the 06.50 train is no longer an option” – but even that was standing room-only as so many relied on it.
“The service is an absolute sham, despite the increased prices we pay in the north east. It would appear that the main reason for all the delays is the sleeper service which consistently runs late.
“It’s about time Scotrail did something about actually providing the service we pay so much for.”
Mr Yousaf said he understood the frustrations caused by delays.
He said: ”I can reassure rail users we are focussed on ensuring the iconic Caledonian Sleeper remains one of the best performing long distance operators in the UK and building on this even further.”
David Simpson, production and safety director for the Caledonian Sleeper, said in May 93.5% of its services ran on time, the best in the UK.
“We are extremely proud that our Right Time performance has improved by 4% over the last year to an annual average of 80.2%. This is currently the best of all long distance operators,” he added.