rear speakers don't work
I need advice on how the get a pair of rear speakers working.
I recently bought a set of Logitech z-640 speakers. These are a 5.1 set (2 front, 2 rear, 1 center, and 1 sub). These replaced a standard set of left/right/sub speakers. The sub and the front speakers work fine. The rear speakers are silent.
System: Asus A7v266 mobo w/c-media onboard sound, 512mb ram, AMD XP1700. RedHat v8 is loaded, 'everything' was installed.
I tried all combinations of the 3 audio jacks into the 3 ports on the mobo. Nothing comes from the rear set. There was one combination which made the rear speakers work, but that disables the front set. The speakers are not the problem.
Any tips on what drivers, config changes, etc might work? Will a separate soundcard (ie, SB Live...) do the trick? I don't care if surround sound works, I just want all the speakers to work.
(I saw some other posts here concerning other soundcard problems. These don't apply because I do have a working sound server, I can play cd audio, and test sounds / system sounds are ok)