Well, I got the Ultra version (rather than BD Express) installed and I am showing LPCM 6 channel output on the PDVD9 status dashboard on a couple of discs that I am playing with (i.e. Valkyrie, GI Joe, etc.). But here is a problem. the 2 rear channels are coming into the AVR as Surround Backs when they should be coming in as Surround Sides when it is a 5.1 or LPCM 6 track. If I use the decoded stream (which is down to DTS 5.1) they do as expeced and come in as Surround Sides....but in the PCM mode they are coming into the amp as Surround Backs. This is wrong. Is there some configuration in PDVD somewhere? You aren't supposed to be getting signal in the Surround Back speakers for a 5.1 track.....and furthermore, it causes a problem because the reason that LPCM is preferred by me over uncompressed Dolby TrueHD or DTS-HD MA (not to mention the fact that my AVR will not decode the HD audio codecs) is that if you get a LPCM 6 input (5.1) as so many Blu-Ray discs are, you can then choose to matrix in the amp and get use of all the speakers... you can't do this if it comes in as bitstream (this has nothing to do with the HTPC...just a design in the AVR).
But back to my real question here, what up with signals that are supposed to be Surround Side coming in as Surround Back?