Audio Device is Disabled

Hi Baban42,

Welcome to Microsoft Answers Forum.
THIRD PARTY DISCALIMER:
The third-party products, information on 3rd party websites, or drivers created by 3rd party companies that have been discussed are manufactured by vendors independent of Microsoft; and we make no warranty implied or otherwise, regarding these products so use at your own risk.
Note: Using Third Party Software, including hardware drivers can cause serious problems that may prevent your computer from booting properly. Microsoft cannot guarantee that any problems resulting from the use of Third Party Software can be solved. Using Third Party Software is at your own risk.

As I understand the red X mark under the device manager tells that the drivers have not been installed properly, In the first place I would suggest you to contact the Audio manufacturer and try to get the latest drivers for your Audio device that is compitable with Windows Vista and install it.However you need to contact your Audio device manufacturer and get the latest updated drivers for your audio devices.  However, I would suggest you to perform a system Restore and check if it helps you get the sound back. To restore the operating system to an earlier point in time, follow these steps:
1. Click StartCollapse this imageExpand this image, type system restore in the Start Search box, and then click System Restore in the Programs list.Collapse this imageExpand this image
If you are prompted for an administrator password or confirmation, type your password or click Continue.
2. In the System Restore dialog box, click Choose a different restore point, and then click next. 3. In the list of restore points, click a restore point that was created before you began to experience the issue, and then click Next.
4. Click Finish.
Note: When you use System Restore to restore the computer to a previous state, programs and updates that you installed are removed.
Refer to this link for step by step procedure to System Restore
http://support.microsoft.com/kb/936212
The computer restarts, and the system files and settings are returned to the state that they were in at the time that the restore point was created.

However you can install the same program in Vista compatibility mode if there are no updated drivers for windows7, the following steps will help you to install the drivers in vista compatibility mode.
1.Right click on the icon for the program
2.Click on properties
3.Now click on compatibility TAB
4.Under compatibility section,  put a check mark on “Run this program in compatibility mode for:”
5.In the drop down box select windows Vista
6.Under privilige level check mark "Run this programs as an administrator"7.Click on “Apply”
8.Click on “OK”

Additional Information: http://windows.microsoft.com/en-us/windows-vista/Make-older-programs-run-in-this-version-of-Windows

Hope this helps. Let us know the results.
Thanks & Regards,
Vijay – Microsoft Support