Beyonce on the controversy
“I am a perfectionist. One thing about me, I practice until my feet bleed, and I did not have time to rehearse with the orchestra. It was a live television show and a very, very important, emotional show for me – one of my proudest moments. Due to the weather, due to the delay, 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 am very proud of my performance.”
you can hear the beyonce's vocal and pre-recorded vocal clearly.
Ian Shepherd – Mastering engineer & producer
http://productionadvice.co.uk/beyonce-didnt-lip-sync-at-the-inauguration-but/
http://productionadvice.co.uk/did-beyonce-lip-sync-the-final-update/