Roland VariOS USB Driver Ver.1.1.0 for Windows XP / Windows 2000 For Product(s): VariOS This is an Roland VariOS driver for Microsoft(R) Windows(R) XP Home Edition/Professional and Microsoft(R) Windows(R) 2000 Professional. Features Multiclient support As many as four applications can simultaneously use each MIDI OUT/MIDI IN port. Simultaneously use four units Up to four VariOS units can be connected to a single PC via USB. For Operating System(s): WindowsXP / Windows2000