After you resume a Windows Vista-based computer from sleep or from hibernation, and then you restart the computer, a high definition audio (HDA) device may no longer work. The device may be a sound device or a modem. You may see an “X” character appear on the speaker icon in the notification area.

Because of this problem, you no longer hear any sound, or you cannot use the modem. This problem occurs even though you have installed update 929685.

For more information about update 929685, click the following article number to view the article in the Microsoft Knowledge Base:

929685 A high definition audio device may no longer work after you resume Windows Vista from sleep or from hibernation and then restart the computer