Airfoil allows you to send any audio to AirPort Express units, Apple TVs, and even other Macs and PCs, all in sync! It's your audio - everywhere. With Airfoil you can take audio from any application and send to your AirPort Express units, as well as Apple TVs, and even other Macs and PCs running Airfoil Speakers! Transmit audio from RealPlayer, Windows Media Player, QuickTime Player, and other media players. Send audio from web-based applications like Pandora, Last.fm, and other to the AirPort Express. You can even stream audio from audio devices like RadioSHARK, XM and Sirius radios, around your house.
Requirements
Intel, Mac OS X 10.6 or later.
Version 4.0.2:
The Instant On component has been updated to prevent a rare lock up.
Airfoil now offers a Deselect All Speakers menu item.
Airfoil Video Player has been updated for compatibility with Flash 10.2.
Fullscreen playback in Airfoil Video Player's web mode has been rewritten for better performance on some hardware.
Popup windows in Web mode are now blocked rather than taking over Airfoil Video Player.
The size and location of Airfoil Video Player's main window is now saved across sessions.
Screenshots destined for remote speakers like Airfoil Speakers Touch and Apple TV are now generated when the target application first produces audio.
Performance of metadata updates sent to Airfoil Speakers has been improved.
Airfoil's network load has been smoothed by throttling packet transmission.
Airfoil now gathers anonymous statistics about the kinds and quantities of speakers in use.
AppleScript now returns the proper volume level for the Computer speaker when linked to system volume.
Applescript update: "applicationSource" sorting has been rolled back to return apps the way it did prior to Airfoil 4.0.1.
A bug where silence might be transmitted when switching targets without Instant On installed has been corrected.
To avoid confusing AirPort Express units, Airfoil no longer sends set-volume commands during its initial connection.
A better error is now provided when a second copy of Airfoil attempts to connect to an in-use copy of Airfoil Speakers.
A rare crash in remote control support caused by network errors has been fixed.
Several rare crashes related to memory management issues have been fixed.
An extremely rare bug that could result in incomplete data being sent over the network has been fixed.