I was in another room and was only half listening so am now wondering if they were talking about tonight's speech or some other situation.
But thought I heard someone report that they had loaded up the teleprompter with an old speech (just using it for testing purposes) and forgot to reload with tonight's speech. And Obama's aide had put his reading glasses somewhere else so it was difficult for him to read from the paper version due to the small type. When asked what he would do he said something to the effect of "well, I guess God is testing me...here goes".
On edit: Nope not Obama. Found the story online. It was Bill Clinton:
Sixteen years ago this month, a youthful Democratic president with a job-approval rating hovering around 50 percent stood before Congress to make an impassioned plea for health care reform. As Bill Clinton mounted the rostrum and looked out over the House chamber, he discovered to his horror that a seven-month-old speech on the economy was whirling through the teleprompter instead of the health care text. For the next seven minutes, until the correct floppy disk was inserted into the teleprompter, Clinton confidently vamped before Congress and the nation as if all were going rhetorically exactly as planned.
http://www.politicsdaily.com/2009/09/09/obamas-healh-care-pitch-can-he-close-the-sale/