It's a weird problem with Intel ICH9 chipset and Windows XP (both x32 and x64)
in some HP Pavilion dv7-1100 series (64 bit).
After starting the system Windows XP will not see the Audio Card that is "attached" to the
High Definition Bus. We discovered (after a big headache), that the problem is related to the
"Microsoft UAA Bus Driver for High Definition Audio" device. The only way to make it work is,
after startup, disable the "UAA Bus Driver" and then re-enable it. After that, the system sees
the audio card and starts using it. We don't know if the problem comes from the Intel Chipset
or from the driver of the "Microsoft UAA Bus for High Definition Audio".
So, while we're waiting for Intel or Microsoft to solve this, I'm going to write a small utility or a batch
file, using the "devcon.exe", to disable and then enable the "Microsoft UAA Bus Driver for High
Definition Audio" at startup.
As I usually say: There is, allways, more than one way to solve the same problem.


>>Many Thanks Al.
>>Your direction was right on target.
>>That is perfect for me.
>>Again, Many Thanks!
>>
>>>>Hi.
>>>>Is it possible to disable a windows device programmaticaly?
>>>>And then re-enable it? For example, the "Network Card"?
>>>>The device that I'm interested right now is listed in the Device Manager
>>>>as "Microsoft UAA Bus Driver for High Definition Audio"
>>>>Any idea will be appreciated.
>>>>Thanks in advance!
>>>
>>>You might get some ideas from http://support.microsoft.com/kb/311272
>
>Glad it will work for you!
>
>Just out of interest, can you tell us why you need to disable and enable devices?