One of the greatest strong points of Apple is that they make stuff that kindles people’s interest, so much that users try to improve the products on their own. Airport express is one such product that allows you to stream audio wireless from iTunes to any set of speakers attached to the airport express audio port. Now one would be thinking what if they could allow me to stream other audio content from my Mac via airport express independent of iTunes? well enter Airfoil. Your wish has just been granted. Airfoil allows you to stream audio from the entire system or from specific applications to the airport express unit. However the only disadvantage that i could mention is that it does not support video!! because of the lag in the audio synching between the system and the airport express unit which would be irritating while watching video. A work around that i use makes use of airfoil and the VLC media player.Basically I route my system or VLC audio via airfoil and then set up the audio desynchronisation function on VLC to compensate the delay in the audio buffering time.This option can be found under the preferences>audio section where one has to enter and negative integer to desync or resync the audio and video.You have to play around with the value here which i believe would differ from system to system.I use a desync of -3350 to get a perfect synch between the video played on VLC and the audio streaming via airport express. I am not aware of such a desync function in other media players, but am interested to know 😉
I just noticed that Airfoil has been updated and solved much of the troubles that you had to go through to play videos! (atleast on the Mac) Check it out.
The mac version of Airfoil now comes with a built-in Airfoil video player (see below!) that takes care of audio sync while playing videos so Mac users enjoy, Windows users you can make use of the above mentioned work around for streaming movie audio.