Hmm, I dont have a mac but I had a similar problem when I first got my bcr2000. I don't know if mac osx installs some sort of legacy usb driver or something like windows does, check to see which driver you are using. If the OS installed a default, try installing the usb driver from behringer, and if its the behringer driver try and just use a legacy or os usb driver. In my case the usb wouldnt work with THE CURRENT BEHRINGER driver. Once I switched to the generic usb driver all was well. Also try switching which usb port you are on ESPECIALLY if you are on a laptop. Sometimes the computer doesn't like certain ports. Best of luck. Trev
