The problem with the faster speeds of some disk controllers is that they keep the PCI bus monopolized for (relatively) long stretches of time. The Digi 001 and Mix audio engine requires consistent periodic access to the bus, and will starve when held off for too long. This results in the familiar (to some) -6042 error ("PCI Bus too Busy").The problem is not that the Digi 001's or Mix PCI card cannot accept data fast enough from the disk controller. In fact, data does not flow directly between the controller and Digi 001 or Mix at all. Rather, audio data from the disk gets sent to system RAM, and then (after being processed by the CPU) gets bus-mastered over to the Digi 001/Mix at an unrelated rate.