Audio problem: When Xander, Willow and Ampata meet up at The Bronze, the song the band is playing is at the point of a guitar solo. If you watch Oz (who has already been established as 'lead guitarist') on stage in the background; he's blatantly NOT playing that solo. The hand movements don't match up.
Audio problem: Jenny prints off the translation for the Ritual of Restoration from her computer, then spots Angel sitting across the room from her. As she gets up and starts walking towards him the sound of the printer can be heard but the paper has already finished printing.