5.1 audio support in Bioshock and/or TF2

My Sound Blaster Audigy 2 ZS has a stereo output jack labeled Center/Subwoofer. The left (white) channel is for the center speaker and the right (red) channel is for the sub. The center channel works just fine but I don't hear anything in the sub channel when playing either Bioshock or TF2, even when I have "5.1" selected in the audio options.

I'm curious if anyone else has a 5.1 setup similar to mine and, if so, if their sub if working in either of these games. Note that I'm running Vista (on that hard drive, at least) and when I use the built-in test utility where you click on each speaker to hear it, I do hear bass from the sub when I click it's icon. So this makes me wonder if these games truly support 5.1 (the .1 is the sub) or if they're just 5 channel (center, front left, front right, rear left, rear right).

Red is microphone. I believe Orange is sub.

No, the microphone is pink. The mic is working so I'm certain of that.

I'm also confident that my wiring is correct, since the Vista test (with the speaker icons) made a sound on the center channel speaker when I clicked that icon, and it made a sound on the sub when I clicked that icon.

My question is for anyone running a 5.1 system on their PC who has either Bioshock or TF2 installed. Is your sub working in these games with 5.1 selected in-game?

I ran the BioShock demo and run TF2 all the time with no surround problems. I am under XP though which does change the landscape somewhat. Are you able to run Creative Mixer under Windows Vista? I used to run an Audigy 2 (now on X-Fi which was a mistake) and I know that Creative's mixer had its own speaker setting that would override the game.

Yes, no problems using completely onboard audio.