It happens relatively frequently that some system update might create conflict with drivers of third-parties peripherals or some other parts of the hardware. According to a report from Cédric, one of our readers, the recent Audio update dedicated to the Mac Pro and aiming to fix the CPU overload problem when playing audio files might have created a new conflict with Firewire audio interface. Indeed, when using a audio interface plugged on the firewire port, the computer will emit a constant and high pitched sound a really serious problem when using such Mac Pro for audio recording systems A dedicated subject has been opened on the Apple discussion forum, and it seems that the problem is affecting at least 3 different Firewire audio interface: http://discussions.apple.com/thread.jspa?threadID=2339757It seems that Apple engineers will have to work again on the audio firmware of the current Ma