NEW YORK, NY  [Wednesday Oct.27.2004]  /Mix103FM.com/ -- Ashlee Simpson says "severe" acid reflux disease and her doctor's warning not to sing, led her to lip-synch on "Saturday Night Live."

The singer told MTV that she suffers from chronic acid reflux disease and that she "completely" lost her voice hours before she was to perform. Simpson said her doctor told her not to sing because she would damage her vocal cords. Said the singer, "My dad was like, 'I'm sorry, you have to sing along with the backing track.'"

About 35 seconds into her second song, "Autobiography," Simpson left the stage when the vocal track for "Pieces of Me" started playing (while she held the microphone at her waist).

Simpson told MTV's TRL, "It's so embarrassing because it sucks. The total situation was a bummer. I made a complete fool of myself." She added, "I was so upset because I have never done that before. But my voice wasn't strong enough. I couldn't even speak."

Simpson's father and manager, Joe Simpson, explained to New York City radio station Z100 FM, "We made the decision to pull up backing tracks to help her push through the song, because otherwise she would've sounded just like a frog--and no one wants to hear a frog on 'Saturday Night Live' unless it's a skit." He added, "If the worst you can find [on Ashlee] is that she got sick and had to use a backing track to help her, well, God bless her."

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