I've been using the cable that came with it. I don't actually know if it is possible to use a firewire or USB interface - I'll look into that.
To be honest H, I'm not sure if you can use a interface either, I was kinda just thinking aloud.
Probably not possible I'll bet. I do tend to use that cable when running through Amplitube, just for convenience more than anything. Seems to work well for that.
As for Rocksmith,, I might see if I can get hold of a cheap copy of 2014 for the Xbox 360 and try it out, it must be an improvement to the original version. We'll see.