Yeah they probably are not consistent. But all I am suggesting, and would be perfectly happy with, is something that doesn't require you to know or even care what they are: if there are multiple streams containing different channels of audio (in this example, probably four streams each with two channels), an option "somewhere" for a custom audio processing that encodes 5.1 from whatever pid:channel the user decides to assign to each of 6 positions. I hope that makes sense. If I was good at graphics I'd draw a picture of what the popup would look like.
Upon thought, the "somewhere" would probably be as an additional option in the green-button popup that lets you select the audio pids. If there's more than one, add a "Combine" option at the bottom which leads to a box containing six fields [LeftFront, Center, RightFront, LeftRear, RightRear, LowFreq] and each of these could contain the designation of one channel from one of the existing audio pids. With the default if you haven't changed it yet being LeftFront and RightFront as L and R from the first pid, and the others empty.
This has the advantage of tasking the user, instead of you, with figuring out which audio channel goes where. And it's obscure enough most casual users probably wouldn't find it. Just one more feature that would set this box apart as more advanced than any of the competition.
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