Khan Off-Key at VMAs Due to Strained Vocal Chords

If you thought Chaka Khan (search) sounded a bit off-key during her performance with rapper Kanye West at the MTV Video Music Awards (search), you were right.

The R&B diva is blaming strained vocal chords for her screeching performance at Sunday's awards show in Miami.

A statement released Tuesday by her publicist, Brit Reece of PMK/HBH, said Khan had to cancel a performance in Park City, Utah, Friday night because her voice was strained and she was under doctors' orders not to perform.

However, she "received a cortisone shot just hours prior to her VMA performance to honor her commitment to Kanye West (search)."

Reece said the shot helped her a bit, but she still struggled through the performance of "Through the Wire," which contains a sample of Khan's old hit, "Through the Fire."

Reece said Khan's voice has been strained because of intense recording for an upcoming album due out in October.

For now, Khan is resting her voice, not speaking.

"She's supposed to perform this weekend in the Bahamas, and as of now she is going to do it," Reece told The Associated Press. "She's resting her chords completely this week."