If a sound device is enabled in your virtual machine configuration, you can connect/disconnect it while running the guest OS.
Note: If the guest OS is started with the sound device disabled, you should shut down the guest OS first, then enable the sound device in the Configuration Editor (select the Enabled check box in the Sound Options tab) and restart the guest OS.
To connect or disconnect the sound device, you should do the following:
Note: There is another way to connect/disconnect the sound device. Right-click the sound device icon on the status bar to display the context menu and select the appropriate command.