Sometimes the device will show up as AV/C subunit in Windows Device Manager, or it will show up properly but still exhibit this problem. To fix, try this:
1. Go to Device Manager in Windows (Right click My Computer->Manage->Device Manager) and expand Sound Video and Game controllers.
2. Right click on the Presonus unit listed in the devices, click properties.
3. Click on the driver tab, and if the vendor for the driver is listed as Microsoft, you need to click Update Driver.
4. The system should give you the option to manually select the driver you would like to use.
5. Click the box that says look for the device driver in this specific location, and choose (may vary depending on where you installed the drivers) c:\program files\Presonus
6. This should then ask you if you are sure, as it may not have been signed or pass Windows Logo testing, choose yes.
7. This should update the driver to use the presonus driver and not the Windows driver.