Yeah, you can tell the DVD versions have better sound and vocals, they power it up. When watching the TV versions I'm often surprised how the sound seems quiet and her vocals are really raw.

As for lip-syncing, during AT2005, during my name's WOMEN they used her track vocals for one line, when she was doing a high sound and just couldn't sing a normal line at the same time. Doesn't really qualify for lip-syncing, but anyway...

You could tell she was sick cause she couldn't hit high pitches and when she did hit high pitches, there would be no sound.