Dolby Digital allows any number of channels to be used. As obie points out, most cable broadcasts and many satellite broadcasts use Dolby 2.0 -- which is just "stereo" with a new name. Pro Logic II can give a very convincing "near DD" effect, particularly with Pro-Logic encoded tracks (such as the DD 2.0 tracks you are getting on HBO). I've never noticed the second line of display when turning PLII on (I generally leave it on for the cable input), but it sounds like the 950 is telling you the truth -- it is using PLII decoding to create a 3/2.1 (or 5.1) signal from the DD 2.0 source. After a could of seconds, it should quickly settle back to:

VIDEO2 DPLII-C
OPTICAL1 -10

That means that the source is now being decoded with Pro Logic II (it's still a DD 2.0 source, but the 950's telling you what processing it is using rather than what the original signal is); it will continue to use PLII on this source until you change it to something else or the input signal changes to a DD 5.1 signal (which PLII can't work with, as Garrett points out).

The volume punch-through confused me a little at first, too (in fact, I initially learned the volume commands to each device using my old 1050's remote). You have to set punch-through on each device that wants to use it. Unlike some universal remotes that have a single "on/off" sort of function for punch through, the 950's remote allows you to enable punch through only on the devices that you need it for. Side effect: if you want it for all of them, you have to turn it on for each of the seven other devices. So to enable punch through on the SAT device, press "SAT" and "MUTE" together, then press "VOLUME UP", then press the "AUD" button to assign the volume up/down and mute buttons from the "AUD" (950) to the "SAT" device. Repeat for the other device buttons in place of the "SAT" button.

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