SoundStay
Utility for Mac OS X 10.5 or later that stops the audio output from going to sleep.
DOWNLOAD 234 KBSoundStay is a utility for Mac OS X 10.5 or later that stops the audio output from going to sleep. On some macs the output turns off automatically after 30 seconds of no audio, causing a popping noise, and a delay before a sound plays while the output wakes up again.
SoundStay prevents both these issues.
Please note that due to the nature of the task, SoundStay will also prevent the system from sleeping automatically.