Vista has brought a new way of 'protecting' audio/video content from
unauthorized copying (a.k.a. copyright infringement) that has limited the
functionality of many audio and video peripherals. 

According to http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.html 
there is much disabling of functionality introduced by Vista's new audio/video
content protection features. The most obvious is the loss of the Stereo Mix
function (ability to record "what you hear") in most soundcards. This is not 
a technical limitation of the product, it is purely a by-product of Vista's 
new content protection features.

Another common problem is difficulty in getting the AC3 Pass-Through to work
through the optical S/PDIF Output (Toslink output). You may need a newer
version of your DVD playing software in order to get this to work. We have
thoroughly tested the S/PDIF Outputs on our soundcard products, and they all
are able to pass Dolby Digital or dts encoded digital audio with no problems.
Vista does limit the sampling rate to 48kHz, however. 

We still recommend Windows XP for 'mission critical' audio home entertainment
and video capture/editing work. Windows XP is stable and has proven to be a 
great platform for home entertainment PC use. If you really need to get
something done using our products for audio or video content recording or
editing, it's still best to do it on a PC running Windows XP (Home or Pro 
seem to work equally well). We do not have full support for the x64 versions
of XP or Vista.
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