I know it says that but it doesn't happen. I do not have rear surrounds either. But still sets itself to IIx. I don't know enuf about the modes to know but I do wonder whether or not I am losing signal if the processor is pumping IIx but no rears are installed. If IIx is for 7.1 emulation and it converts to 5.1 when rears are turned off why not display it?

From what I have come to understand, PLIIx can apply even in cases where there are no surround back speakers - it simply makes use of the available speakers (sort of as if Dolby could replace PLII entirely with PLIIx, but have for whatever reason allowed PLII to co-exist while doing the same thing for systems with no surround back channels).

That's ok then. I was looking on the Dolby sight but it doesn't really give too much detail on the differences.

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