Audio problem: When Comicus is announced in Caesar's court, the trumpeters play "Hooray for Hollywood". Notice that the music starts before they get their instruments to their mouths.
Audio problem: During the "Shock Treatment" musical sequence, look carefully at Dr. Nation McKinley's (Patricia Quinn) lips at the end of her solo speaking part. She mouths words to the song, even though the only voice you hear is Dr. Cosmo McKinley's (Richard O'Brien).