You open the properties dialog box for an audio device in the Sound control panel on a Windows Vista-based computer. You may then find that duplicate entries are listed in the Default Format list on the Advanced tab of the properties dialog box. Also, when you select one of the entries, and then click Test, you may receive an error message that resembles the following:

Failed to play test tone

Note: You may receive a different error message, depending on your hardware.

After this problem occurs, you may be unable to use other programs that play audio. For example, programs such as Windows Media Player or Windows Media Center do not play sounds correctly.

This problem may occur after you change the entry in the Default Format list for the device. To open the Default Format list for the device, follow these steps:

1. Click Start Start button , type mmsys.cpl in the Start Search box, and then click mmsys.cpl in the Programs list.
2. Click an audio device that is listed, and then click Properties.
3. Click the Advanced tab, and then note the items that are listed in the Default Format list.