From CBS News:
...The outdoor crowd was so massive that many were unable to hear Palin speak, so about midway through the Alaska governor’s remarks, some of them tried to take matters into their own hands, shouting in unison, “We can’t hear you!”
When that didn’t get the candidate’s attention, they tried a new tactic. “Louder!” they shouted.
Palin appeared flustered as she stopped reading from the prepared remarks, which were coming across her teleprompter. “I would hope at least that those protesters have the courage and the honor of thanking our veterans for giving them the right to protest!” she admonished the confused crowd.
Palin’s husband Todd tried to put an end to the awkward episode by approaching his wife on stage and telling her, “They just can’t hear you back there. That’s it.”
Palin responded, “OK. I’m doing that,” and then continued with her stump speech.