We’ve been asking around, and we have been downloading driver after driver and swapping sound cards all day long to no avail. Vista’s digital audio support is completely broken in this latest build. To be fair, it is not a CTP, but on the other hand, besides the lack of digital audio support on Microsoft Windows Vista Build 5342, it seems that the audio stack is exactly the same as that of 5308.
These comments are not made on whim nor are they fallacies in induction, NeoSmart Technologies carried out the most extensive review and troubleshooting guide for both digital and analog audio on 5308 (February CTP) which can be seen here.
As far as we can tell, the problem lies in the audio preprocessor. In previous builds, if the drivers used were not suited to digital audio, the signal would attempt to be forced through and the speakers would not recognize it. However in build 5342, it seems that the audio stack does not send the arguments from the preprocessor to the digital out correctly, backed by the fact that analog speakers will pick up the sound no matter what settings are used; whereas if the signal was being sent in digital, no matter who malformed, a analog speaker could not possibly output the sound.
A possible workaround would include drivers that by default use digital output, not in the sense that the digital out checkbox is activated by default but rather that the card outputs a digital signal unless told otherwise.
While this is the first Vista build that one can use without treating it in a very fragile manner, and it actually feels like a production OS, the lack of digital audio is a heavy blow for any audiophiles or music addicts and producers. It means that Vista’s highly touted media center abilities are in deep trouble, and that gamers and movie lovers alike will have to unfortunately pass this build up.