Couric, who took part in the satellite Q&A from New York that included colleagues Bob Schieffer and Jeff Greenfield, also called such talk inaccurate.
"We have no plans to part company any time soon," Couric said.
She dismissed what she called speculative reports that have "spun out of control" and called the attention to her job status "befuddling."
Pessimistic predictions about Couric's future arose less than a year after she took over the newscast in September 2006. Despite changes in the producer and focus, the show has consistently lagged about 2 million viewers per night behind NBC and ABC.
Schieffer, who served as interim anchor between Dan Rather and Couric, defended the program.
Compared to the other network newscasts, "we measure up very, very well," Schieffer said. "The right stories are getting on that broadcast, the right interviews. ... And I'm very proud to be part of it."
Questions were raised whether plans by CBS and the other networks to send their anchors overseas to cover Barack Obama's trip to Europe and the Middle East are justified or reflect media infatuation with the presumptive Democratic nominee.
McManus defended the decision to send Couric to Jordan, saying Obama's journey next week represents more than a campaign event.
"I would call it the biggest news of the week," McManus said.
Obama's foreign policy expertise has been called into question and the trip opens a window on that issue, he said.
Greenfield said he expected reporters to do their job.
"I have a strong hunch the people interviewing Obama will have tough questions. It's not like North Korean television covering (communist leader) Kim Jong Il," Greenfield said.
Couric concurred.
"It's not going to be like, `How do you like the weather in Jordan, senator?"' she said.
