Symptoms
After upgrade from Parallels version 3 to version 4 audio devices are not working any more. The following error is displayed:"Bad Directsound Driver. Please install Proper Drivers or select another device in configuration. Error code 88780078"
Resolution
Please, perform the following operations:- start your virtual machine,
- click on Start -> Control Panel -> System -> Hardware tab -> Device Manager,
- right-click the "Sound, Video and game controllers" node and select "Scan for hardware changes".
Most probably a missing multimedia audio driver will be found. Please, install it.
NOTE: you might need to insert the Windows installation CD to install the driver.