Van de site van Rogue Amoeba (maker van Airfoil):
"When the AirPort Express plays audio, whether sent by iTunes or Airfoil, output is delayed by anywhere from 2 to 10 seconds. When local playback of audio occurs, Airfoil grabs the audio and sends it to the AirPort Express, but the audio will not be heard for several seconds. This delay is caused by the AirPort Express itself, which buffers audio before playing it. Because of this, the AirPort Express is not suitable for use with video."
En: "To put it simply, Airfoil is not recommended for use with video. Because of the way the AirPort Express hardware itself works, there's a delay from the time audio is played locally to the time it is heard remotely. Unfortunately, the issue here is with the hardware itself."