Dolby Pro Logic IIx, stereo and 5.1

[dl8860]

On my newly setup Denon X2000, when I watch HD channels from my Sky+HD box it says it is outputting Dolby Pro Logic IIx, and I can clearly hear that I am getting 5.1, or rather 5.0 through my speakers (no sub yet)

However, when I watch non-hd (with stereo source), it will only output stereo sound, through my front left and right.

But isn't the whole point of Dolby Pro Logic to take a stereo source and split it into 5.1? I can't find any options or settings to override how the amp decodes the audio signal. What am I missing here?

 

[dl8860]

Ah thanks guys, the coloured buttons at the bottom did the job. I just assumed they were gimmicky presets, like the 'football mode' on my TV or something like that