Beyonce has admitted she did "lip sync" when she performed the national anthem on Inauguration Day.
The singer held a press conference in New Orleans on Thursday, days ahead of her half-time performance at the American football championship Super Bowl.
She said she is a "perfectionist" and wanted her performance for President Barack Obama to be a memorable one. She called the day "emotional".
Beyonce opened the press conference with a live rendition of the national anthem.
"I practice until my feet bleed and I did not have time to rehearse with the orchestra," she said. "Due to no proper sound check, I did not feel comfortable taking a risk.
"It was about the president and the inauguration, and I wanted to make him and my country proud, so I decided to sing along with my pre-recorded track, which is very common in the music industry. And I'm very proud of my performance."
She asked those at the conference to stand before she belted out The Star Spangled Banner, and after she said with a laugh: "Any questions?"
The star had not spoken publicly since it was alleged that she lip-synched her rendition of The Star Spangled Banner at Mr Obama's inauguration last week.
Her critically praised performance came under scrutiny less than a day later when a representative from the US Marine Band said she was not singing live and the band's accompanying performance was taped. Shortly after, the group backed off its initial statement and said no one could tell if she was singing live or not.