Even with the latest version of Windows 7 and VirtualBox 3.0 available, there is no sound drivers for the emulated sound card bundled, unlike in Windows XP. To enable sound in Windows 7 under VirtualBox you need to install the drivers for the sound card.
Instructions:1) Go to RealTek’s website: http://www.realtek.com.tw/
2) Click on “Downloads”, then on “AC’97 Audio Codecs”. On the downloads page download the file with the description “Vista/Win7 (32/64 bits) Driver only (ZIP file)”.
3) Extract the file and run setup.exe. You will need to click on “Install anyway” a few times.
4) Then the device manager should refresh itself, and the sound card should be installed and working.
