vb code for composite usb device

our device
- USB device uses TUSB3200 microcontroller and a codec
- it has 4 interfaces: audio control, audio streaming in, audio streaming out and hid (numbered in the same order)

Software
- used usbhidio code from www.lvr.com.
- this helps in device detection and only refers to one interface
- set_interface supported by only Windows CE

Problem
- How do we refer to remaining 3 interfaces?
- where can we find dll's for the same and how do we use them in VB?

Note: coding is in VB