I have just installed a new Windows 7 with my Macbook pro and just solved the sound card problem. However, my Bose Companion 5 (USB Audio) still does not work.
The device manager can find BOSE USB AUDIO, however, it said can not find the driver for this device. I have tried to copy the usbAUDIO.sys from windows vista 32 bit. However, it still can not be recognized.