Beyoncé's Anthem Performance Prompts a Flurry of Analysis Did she or didn't she? A day after a spokeswoman for the United States Marine Band suggested that Beyoncé may have lip-synched her stellar rendition of the national anthem at President Obama's inauguration, the R&B star still had not made a statement, and the Internet was abuzz with theories, as people reviewed videos of her performance for clues. "This is getting as much analysis as the Zapruder film," Joe Moore, the program director at Valley Public Radio in Fresno, Calif., wrote on Twitter. He was referring to an analysis of the performance by a British audio engineer, Ian Shepherd. Mr. Shepherd pointed out that in some videos, like one posted by The Wall Street Journal, a second vocal track can clearly be heard, suggesting that Beyoncé was singing along to her own recording. But Mr. Shepherd added it appears the vocal that the audience heard was the live version. He pointed out that her voice was hard to hear when she began, then became louder, a sign that the sound engineer may have turned up her microphone. At another point, he said, her voice gets brassy when she leans closer to the microphone. He also pointed out that Beyoncé removed her earpiece monitor nearly 2 minutes into the song, suggesting that she was having trouble hearing the pitch of her voice through the monitor, perhaps because she was hearing the recorded version. "None of these clues are conclusive," Mr. Shepherd wrote, "but to fake all of them, plus the details of the performance itself, would make Beyoncé the best lip-synch artist in the world!" The idea that Beyoncé, one of the most gifted and technically accomplished singers of her generation, might have prerecorded the anthem drew a strong reaction from music fans on social media. Opinion was divided between people who felt it should not matter if the performance was live and those who felt betrayed. Several other vocalists expressed support. Aretha Franklin, 70, who sang in bitter cold at President Obama's first inauguration in 2009, said she laughed when she heard that Beyoncé might have prerecorded the song. "I think it's optional really, it's up to the artist," Ms. Franklin told ABC News. In 2009, I wanted everything to be live and on the real side, for the moment, as it actually happened. Those were my feelings for my performance, but having come face to face with 28, 22 degrees I am not surprised she pre-recorded. She wanted her performance to be what she wanted to be and she realized it wasn't going to be the way she wanted it to be or she was going to be running a risk. Yvette Noel-Schure, a publicist for Beyoncé, did not return several telephone calls and e-mail messages on Wednesday from a reporter requesting information. Matt House, a spokesman for the Joint Congressional Committee on Inaugural Ceremonies, which staged the swearing-in and Beyoncé's performance, also declined to comment. On Tuesday, the Marine Corps said the Marine Band that accompanied Beyoncé was told at the last minute that she would use a recorded version of their parts. That decision was made, a spokesman for the corps said, because the singer had had no time to rehearse with the band. So the Marines, who had performed for two hours without trouble, mimed playing their instruments during the song. Officials in the Marine Corp press office also confirmed Beyoncé had recorded a version of the anthem on Sunday night at a studio in Washington. That recording was to be used in case of bad weather or equipment failure.