dont know what when wrong but I cannot access my audio devices control panel. Control Panel...Hardware and Sound..Manage Audio Devices. Nothing happens. Only a brief flicker. I also cannot change system sounds. Any idea what could be the problem?

If the sound is working properly, this can be caused by third party software installed. According to some users' feedback, this may occur if old version of Skype is installed. Therefore, if Skype is installed, please go to Control Panel -> Programs and Features to uninstall it. For more information, please refer to this Skype article: Why does Skype crash on my computer? If the issue persists, please access Clean Boot to check the issue. If the issue disappears in the Clean Boot environment, you can continue to narrow down which entry is causing the issue.