I haven't, but that's something I could try. I installed XBMC and for the most part this appears to output the right audio, and I can change my audio settings to output audio to my TV speakers only or my Receiver depending on what I want at that time. One thing I really don't like about XMBC is I have my TV hooked up via HDMI, and my PC monitor via VGA. My PC monitor is my main monitor, and my TV is my extended desktop monitor. To get XBMC to show up on that display is a pain, the TV has to be on and set to that input, I open XBMC, then select video output associated with that monitor, then it appears. But everytime I turn the TV off, I have to do this all over again.
WMC on the other hand with Media Browser, I can drag that over to the TV monitor, and it either stays there or always goes back to that monitor when the TV turns on. I don't have to drag it over there every time I turn the TV on.
Curious what the pros / cons are for choosing one of the various splitters? The guide makes mention of LAV and Shark, but you mention FFDShow and another post suggested Haali?
LAV was too buggy for me and it wouldn't bitstream AAC audio. So I setup FFDShow in Shark007 codec pack to bitstream all my audio, to include AAC audio. Zero problems since I started using FFDShow (about 8 months now).