I didn't see any posts specifically mentioning how to get surround sound working out of Premiere without an expensive sound card, so here is a successful method.
Problem: You have integrated audio on your motherboard, and it doesn't come with ASIO drivers. So you select WDM as the driver in Premiere, Soundbooth, or Audition. It works fine, that is until you try and output 5.1 audio.
Note: I'll focus on Premiere, because that is where I originally troubleshooted this, but the same goes for the other Adobe products that use sound.
I have a high end motherboard from EVGA, and it comes with Realtek HD audio. It features 7.1 surround sound (8 Channel), sampling rates up to 192 khz, and 32 Bit output up to 192 khz. Not Bad, but not great because it only seems to sample at 16 bit. Remember when 16 Bit CD quality sound was the standard.....those were the days.
If you create a 5.1 audio project in Premiere, mix all your tracks, use the surround sound mixer to place the "puck" where you want the sound coming from, and play it, you only get 2 channels out. Even if you have a surround sound system attached to your computer. By the way, I highly recommend the Logitech Z-5500 system. A bit pricey, but the quality is awesome. The problem is, Premiere Pro doesn't find any ASIO drivers, so you're stuck with WDM. Well, WDM only gives stereo output.
The beauty of ASIO4ALL is that it doesn't change any drivers in your system, it only launches when you start an application that has ASIO4ALL set as the driver. Moreover, It bypasses all the windows gobblygook, and improves latency so you can get rid of the "latency-echo" if you're playing and recording at the same time. It also lets you adjust "Latency Compensation" in it's pop-up settings window. The only drawback I can see is, because it latches right on to the hardware, ignoring windows, it won't let multiple applications use the audio hardware at the same time. But that is by design. It's really a feature.
After you install ASIO4ALL, go to Premiere > Edit > Preferences> Audio Hardware, and select ASIO4ALL as the default device. Then click on "ASIO Settings", and ASIO4ALL will launch and show you what audio hardware you have available. If you have surround sound you should see something like "Out: 8x 44.1-192khz, 32bit." Just make sure it is enabled.
Now go to Premiere > Edit > Preferences> Audio Output Mapping, and you should magically see all your available output channels. Mine shows 8.
One last note: Premiere by default seems to use the L,R,LS,RS,C,LFE arrangement output order. This isn't really standard, so you'll probably need to change it to L,R,C,LFE,LS,RS to get the sound to play on your audio hardware correctly. Just re-arrange the speaker assignment squares to the correct order.
To facilitate your surround testing, I've attached an audio file that plays 5.1 audio, one channel at a time. You'll hear a voice saying the speaker position the sound should be coming from. It is in .ac3 format, and should play in Premiere Pro, and the VLC media player.
Update: I tried to upload it, but the website reported back "The content type of this attachment is not allowed."
Holy cow Adobe, we can't even upload an .ac3 file!!!
Okay, fine. Here is the same 5.1 surround sound test file in wave format.....ooops it's too big, it exceeds the 5.0 MB upload limit.
Now I'm frustrated......Adobe....Why I ought to...... (3 stooge reference.)
If you want the .ac3 file, send me a message with your email address, and I'll try and send it to you.
Hope it works for you.
PS See my other post http://forums.adobe.com/thread/511930, to convert your mixed 5.1 audio to the DVD standard AC3 file that Encore wants, without ponying up for that SurCode Plug-in.
Adobe, give me a break, $300!!!