sound channel problems

[Preacher35]

OK, I'm have issues with missing channels on my sound card and could really
use some help!
First, here's what I've got:
Intel X6800, BFG 680i mobo, 2gb Corsair PC9136 RAM, Soundblaster X-Fi
Fatality sound card, BFG 8800GTX x2 in SLI, Logitech Z5500 5.1 speaker setup.

Problem: I installed Vista Ultimate about three weeks ago. I had a small
hickup w/sound channels being crossed but was able to clear it up w/in
Creatives' THX console by reassigning the channels. HOWEVER, three days ago,
after rebooting, my front left sound channel was missing. Reassigning the
channels did not do any good. I tried to adjust polarites, swapping the
analog cables/ports and to no avail.
I uninstalled the card, drivers and all software, then reinstalled. Same
problem, except now my center/subwoofer channel is not producing any sound
either. I removed EVERYTHING and switch over to my mobo's onboard sound and
go the front right channel back, but the center/sub channel is still missing.
I checked all of my channels on the Logitech Z5500 setup independent of the
PC and they all work just fine. This MUST be a Vista issue.

Any ideas or suggestions? Thank you in advance

 

[Snacko]

This sounds like a layer-1 issue (wires). I'm unfamiliar with your speakers,
but I have most of the same equipment including processor and sound card.
But I wonder if you can put your system in "mono" mode, taking all mixing out
of it. If so, then every speaker should get the same input. If one doesn't
work, then I'd look at either the cable or the speaker itself. swap out
speakers and see if the problem stays where it is or follows the faulty
speaker.

And if you have the opportunity, treat yourself to a mobo upgrade. Mine
died so I got the Intel DX38BT for extreme processors and I'm pretty happy
with it. Warning: You'll need DDR3 RAM, but that's where the performance
increase comes from.