I've been using an original MBox with a PowerMac G4 933MHz for the past two years with no problems, but now I have a mac pro 2.66 and this little box is giving me a headache. Whenever I use the MBox for audio output with any application, after a couple of minutes of use my audio will be interrupted by loud white noise. It doesn't go away until I shut down and restart the application I'm using. I have the Intel versions of Pro Tools LE and Core Audio. I've tried all the USB ports on my machine, even reinstalled OS X. This is driving me nuts, as I never had these problems on my G4. Could anyone offer any help? Thanks!