There's a reason I'm not doing a full-blown HTPC to do everything and this is one of them.
According to what you have posted
, I would have to say it is one of those AFD-Mult mode, either Pro Logic II Movie or Music should do it. On my Pioneer VSX-1018AH, I have to switch to Standard Surround (instead of Auto), and then I can flip through things. I have Movie, Music, and Game DPL-II to choose from.
I can think of 2 things: either your receiver does not do a "best guess" upmixing without a properly encoded stereo signal (technically speaking a "Dolby Pro Logic" needs specially coded stereo data to give enough clues for the receiver to work with), or you are not using proper material to demonstrate this. On my receiver, the DPL-II algorithm is very smart in putting human dialogue to my centre speaker just like a real 5.1 stream. So depending on the scenes in the video/audio that you are playing, sometimes the surround speakers won't get a lot of audio signal fed to it, regardless of upmixing or not. Because my signals are not always properly DPL-encoded, the best guess is going to make the surrounds fairly weak.
The Model M is not for the faint of heart. You either like them or hate them.
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