Yes I have got both Fire wire devices on seprate buss and have got the on Legacy drivers to .... I have come across a post on here about Nivdia graphics cards and latency and i think it has something to do with that,,, Having same problem on my new build studio Turns out it's to do with the graphics card Nivida having priority over say your Fire wire devices (latency) There is a program to fix this called PCI Latency ... but it dont work with win7 so im stuffed. My first thoughts were that my Focusrite drivers were a bit flakey but I sure it's my graphics card pull priority over my Audio & DSP devices