You can Add and delete sounds events in the Control Panel. In order to do that:
1. Open RegEdit
2. Go to HKEY_CURRENT_USER\AppEvents\Schemes\Apps and HKEY_CURRENT_USER\AppEvents\Schemes\Eventlabels. If this key does not exist you can create it and add events.
3. You can add/delete any items you want to or delete the ones you no longer want.