A move to clamp down on ticket scalping has hit a bum note with U2 fans in Vancouver.
Last Friday, long queues formed when the concert organiser had staff checking ticket-holders' identification and credit card details to ensure no one made a quick buck from reselling tickets.
But the checks took time, causing some fans to miss parts of the performance from opening act Mumford & Sons, according to Vancouver's News 1130 website.
Some livid fans later went online to complain that they had waited in line for more than two hours.
The organisers attributed the delays to fan behaviour.
"This was well-intentioned, very well-thought out. There was a lot of planning… (But) we had a large convergence of guests arrive around the same time and that is when the bottleneck became quite significant.
"Obviously, it's not ideal, it's not what we wanted, but when you're deploying new technology… the processing times were not what we had hoped," an employee noted.
"We are extremely sorry that we weren't able to process them quicker but, at the end of the day, we are searching for ways to ensure the right fans who want to see artists are able to do so in a cost-effective manner."
Scalping has also made headlines in Singapore, with fans outraged over the reselling of tickets for British singer Ed Sheeran's gigs here in November.
In Vancouver, the fans were at least somewhat appeased that U2 had held off the start of their show until all ticket-holders had gained entry.
The Irish rockers were rolling out The Joshua Tree Tour to commemorate the 30th anniversary of their first No. 1 album, The Joshua Tree, in 1987.
Lead singer Bono and gang are playing all 11 tracks from that album, such as Where The Streets Have No Name and With Or Without You.
Fans were also treated to a new song - The Little Things That Give You Away - from upcoming album Songs Of Experience.