Chase, the CTA spokeswoman, said Ventra has added staff to its customer service call centers to reduce wait times. She said Ventra customers should use the self-service phone options unless they specifically need to speak with a customer service representative.

CTA and Pace officials are reiterating their position, first voiced in late August, that problems were anticipated with such a major change and that the transition is going "fairly smoothly overall" with only "a handful of issues."

CTA and Pace officials failed to provide data documenting the number of Ventra complaints.

"The rollout is continuing," the CTA's Chase said. About 899,000 Ventra cards have been issued and they have been tapped against readers 10 million times, she said.

Pace spokesman Patrick Wilmot said Pace has received numerous complaints from customers who haven't been able to get through to Ventra customer service on the phone.

"The best thing for people to do is to refer these questions directly to Ventra," Wilmot said.

The CTA signed a $454 million contract in 2011 with California-based Cubic Transportation Systems Inc. to create and manage the new fare-collection system that features contactless Ventra cards to replace older fare card technology. Pace subsequently joined the program, while Metra is planning to test other technologies.

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