OK this is really frustrating and I have been trying to work it our for quite some time now but nothing works. I need any help you guys can provide.

Configuration:
Asus P5B Deluxe
Intel Core 2 Duo 2.13 MHz
Kingston HyperX 8500, 2 x 1 GB DDR2 Dimms
Asus VGA EN7600GT Silent 256 MB
Creative SB Audigy Platinum 5.1 (Yes the old one)
Enermax 500 Watt Power Supply
3 SATA HDDs & 2 Sony Optical Drives on IDE Controller

The problem is that I get no sound from the center channel when using 5.1 configuration for my Logitech Z5450 Wireless speakers. This is what I've tried so far:

1. Formatted my system and reinstalled the devices one by one. The center channel may work from time to time but with no apparent reason it stops after some time.

2. I disabled my Audigy and tried the onboard audio system. Same problem. I reformatted my PC with no Audigy plugged in, just onboard sound enabled. Same issue again.

3. I connected my old Altec Lansing 5100 speakers. Same problem.

4. I changed cables between the PC and the speakers. Same problem.

5. I tried different codecs and players, each time formatting my drive just to make sure that no garbage is left inside. Nothing worked.

6. Upgrading to the latest BIOS did nothing for me.

7. I completed a new format not connecting any unnecessary internal or external devices. Just board device drivers, creative drivers and VGA. Same damn thing even when I did the same thing with the onboard audio and no creative installed.

8. I even tried Vista with beta creative drivers. Same problem.

To sum up:

1. It is NOT a faulty Audigy card because the same thing happens with the onboard audio.

2. It is NOT faulty speakers because I tried my older set with no luck.

3. It is NOT the cabling cause I tried a new set.

4. It is NOT my windows set up cause I formatted my drive countless times using original Windows. Even tried Vista RC1.

5. It doesn't seem to be the board because there are times after a format that the system works flawlessly.

There was one time that I managed to get everything working and thought I had found the reason behind this hell although it did not make much sense. I noticed that when I connected my Logitech USB Web Camera the problem occurred. When I disconnected it was fine. So I left it disconnected. After two days the problem re-emerged with no reason what so ever.

Any ideas? Any...

I thought I should drop analog connection and try digital but I have never done that before. What kind of cables should I look for? I think my Audigy supports digital output through a 3.5" jack (is that the SPDIF I've heard about?) and here are the Logitech specifications.

• Source inputs:
- (2) Digital optical for DVD or CD players, PlayStation®2, Xbox™*, or PC sound cards (requires optical cable, sold separately)
- (1) Digital coaxial for DVD or CD players or PC sound cards (requires coaxial cable, sold separately)
- (1) 6-channel direct (3 stereo-mini connectors) for 2, 4 or 6-channel PC sound cards OR
- (3) stereo-mini connectors for 3 stereo analog audio sources, such as CD and DVD players, PlayStation®2, Xbox™*, or 2 channel PC sound cards (some devices may require stereo mini to dual RCA adapter, sold separately)
- (1) Analog stereo-mini (on side panel of control center) for portable CD, MP3, or MiniDisc® players

This is odd. I have a similar configuration using the same motherboard. My audio is choppy and sounds terrible. I disabled the onboard audio (SoundMAX) and installed a Soundblaster Audigy card. I now have the same problem but worse. Added to choppiness, the sound now skips and delays ala Max Headroom. An external USB Soundblaster device produces no audio at all.
I've tried everything short of an OS reload. I may try that next unless someone has an alternative...

Hi!! THANKS JOHNNYB!!!! Lost three nights of sleep trying to solve this!! I had same problems as yours but with a different configuration. My MB is a P5B Deluxe and i am trying to use Creative X-Fi Fatal1ty Extreme Gamer Pro with Creative Inspire T7900. Disconnecting Logitech USB Webcam, as JohnnyB said, i had my problem solved...i am waiting to see how it will work on next two days. By the way, my starting trouble was no sound from rear speakers and mixed sound between the others. I am also waiting for Creative Tech Support to reply to this question. Keep holding on 'til they reply!!

@cpuf1xer try to disable DTS (with on board audio device) and set "Large Speaker" on the Setup Wizard. I've read this around, and someone solved in that way. Let's try!

I bought an X-Fi Platinum but haven't installed it yet. Having read morgalad's post, the new card won't probably solve my problem and the Webcam thing only worked for a couple of days (hope this is not the case for you too). Any of you people tried a digital setup for audio?

just wanted to thank you guys for the good info.

i was just last night having the *exact* same problem with my surround output ... only my problem was occurring with a soundblaster live 5.1 card ...

as others have deduced, the problem was solved by removing my logitech quickcam pro 5000 from the system.

...

i've since re-installed the camera and camera drivers and have found that as long as i disable the quickcam audio drivers (in system/hardware/devices list) ... then the surround sound and audio otherwise works just fine.

not a bad fix for me as i want to use the camera but could care less about the camera's audio ...