Subwoofer/Center speaker analog not detected

[rutgurt]

I just got a new Logitech 5.1 sound system and I plug in the 3 inputs: green, black and orange. I can get everything to work except the Center/Subwoofer analog. When I go to the RealTek settings in Control Panel where it shows the picture of the the living room, i switch it to 5.1. The rear and left/right front speakers light up under the picture of the different color Analog inputs, but the Subwoofer/Center Speaker doesn't light up. When I do a sound test, everything works, but silence when it is testing Subwoofer and Center.

I've updated RealTek drivers, i've plugged in different anlog inputs into the Subwoofer/Center analog just for the hell of it, to make sure it's not a bad wire.

I am starting to wonder if my motherboard has a defect?

Any ideas? what should I do? this is driving me nuts

 

[rutgurt]

UPDATE: after uninstalling RealTek audio manager and its drivers, the Windows 7 drivers seem to be using all my speakers fine. I went into Playback Devices, right clicked Speakers, and checked the 5.1 Surround option. I clicked Test and sound comes out of all speakers individual in accordance.

Aside from not having all the different options (which I never use) of the RealTek audio manager, will I be at any disadvange by not using it? I am afraid to re-install RealTek drivers, and don't wish to unless I am going to be at any type of sound quality disadvantage.