I bought an Mbox2 today and unable to get it to power up off my NEW ibook G4 (1.42ghz). went back to Guitar Center and they were unable to power up off thier NEW pwerbook (1.67 ghz). both laptops had Protools 6.9.2 installed. THEN we hooked it up to thier imac G4 desktop, without any protools installed, and it powered up! what's going on? :-?