Summary

1) Went to Start->Settings->Control Panel 2) Clicked on the System icon 3) Picked the Hardware tab, then clicked on "Other Devices" 4) Click on the Display devices tree node and expand it 5) Delete the entry for "PCI Multimedia Audio" 6) Reboot the machine 7) It will detect the audio device, simply point it to your MX300 drivers 8) It will a dialog which confirms you want to install unsigned drivers for "Unknown drivers", click Yes 9) It will go away and come back and again, ask if you want to confirm the installation for unsigned drivers for "Diamond MX300", click Yes 10) Reboot and the sound on my system worked Note, towards the end, it seemed not to get the drivers correct, so far as name, but clicking Yes and on the next dialog, it will read "Diamond MX300". But the above steps are what I followed to get it working.