The only way I found to convince Vista to stop looking for 'Multimedia audio controller' drivers was restart into SAFE MODE, remove the entire USB stack from the device manager (USB devices, USB Root hub, USB Controllers), then restart in normal mode and let Vista reinstall everything. The device always identifies itself as 'Multimedia audio controller'. inf file (I told Vista to search through the whole drive C). Choosing 'Update driver.' is a no-way, because Philips drivers do not install any. When I replugged the device in, Vista insisted on installing a 'Multimedia audio controller' instead of the correct 'Philips VOIP321'. That's OK, I aborted the installation, unplugged the device and installed the drivers. The device was recognised as 'Multimedia audio controller', but no suitable drivers were found. The last thought lead me to another test: I restored the fresh Vista Enterprise VM image, then I plugged in the device without installing any driver.

Something wrong during drivers installation on the real PC?.

A different USB configuration? The real PC has an USB audio card, which is not present in the VM.

Vista Enterprise having different drivers than Vista Home? (I wonder why).

The device manager show a 'Philips VOIP321' device and a HID. I expected some problems due to USB emulation or, at least, the same non-working-driver behaviour well, after installing Vista drivers from Philips, the device worked flawlessly, even inside the VM. Since I can't put my hands on the PC with Vista Home till tomorrow, I've made some tests on a virtual machine with Vista Enterprise SP1 as guest.

Usbaudio sys windows 10