To enable the advanced sound effect for gaming, please make sure the setting of the Hardware Acceleration is "full". The directory is as below: Control Panel -> Multimedia/(Win98)/Sound & Multimedia/Win200,Me)/Sounds & Audio Device(WinXP) ->Audio ->Playback/Advanced ->Performance ->Harware Acceleration.
This happens when the on-board sound device and PCI sound card are in conflict. Just disable the sound device in BIOS (or, remove the PCI sound card) and the problem ceases to exist. You could also just disable the appropriate device in Device Manager.
No sound on Windows XP
More sound issues with Windows XP