I've got the exact same problem, and it is not comforting to find that nobody has responded to your post in over 2 years. I can produce 5.1 sound and monitor it in Au CS6 in all its 5.1 surround glory with great panning effects, only to have only Stereo in Pr CS6. I've just started trying to do surround and therefore just discovered this about Premiere, and have a deadline that I'm working against to figure this out. As you found, Pr displays the tracks in a different order than Au, but the content as you also found, is correctly mapped from Au. I believe the file formats contain metadata that indicate what data is on which track so the mapping can be discovered (not sure that is true with AC3, which might assume track order).
At any rate, I have a SoundBlaster Recon3D PCIe audio card (not a high end, and doesn't come with ASIO drivers), so I too tried ASIO4ALL, but couldn't get it to work in either Pr or Au. ASIO4ALL control panel shows only 2x channels for my cards output, instead of 6 (but DOES show 6 inputs!). My Au 5.1 works correctly with the default MME Device Class. Pr has WDM, which is supposed to encompass MME, but no matter what I do, I cannot get Pr to let me monitor 5.1 sound. I only get stereo, and my channel mapping only shows stereo options.
I'm hoping this is a driver/soundcard issue, and not a Pr/Au issue, since I'm not going CC, and Adobe doesn't seem too keen on fixing CS6 bugs.
If you found an answer to the problem, please post it here.
You need an audio interface with true multichannel output capability to be able to monitor 5.1 in either Audition or Premiere. The SoundBlaster only outputs surround from previously encoded audio fed to it in a digital stream. Neither Audition or Premiere output encoded streams. They just produce 6 separate digital audio streams from a 5.1 source which needs a fully multichannel soundcard to convert to analogue.
ryclark, from what I can tell, the Creative Soundblaster card is a true multichannel (5.1 surround) output device. It does have the Dolby Digital Live (DDL) decoder built in so that it can decode Dolby streams on the fly (from DVD and Blu-Ray). I've verified that I can play both an interleaved 6 channel uncompressed WAV file as well as a 5.1 surround AC3 encoded conversion of that same WAV file, in both Windows Media Player and VLC, and both output true 5.1 sound just as it sounds in Au. So, that leads me to believe that the SB is indeed a fully 5.1 capable card. I agree with you that an external interface has much more potential, but I don't believe that the Creative soundcard itself is the issue. Having said that, I am beginning to think that is a 32 vs 62 bit driver issue, since the card works as expected in Au (x32), but not in Pr (x64). I would expect that both Au and Pr share at least some of the underlying code that routes sound to the system (but that might be a stretch).
Thanks for the reply.
Creative must have upgraded their soundcards fairly recently since they used not to be able to stream discrete multichannel audio. Let's hope they have also improved their driver support.