Mono-like output to speakers -- software issue

Friends:

My speakers are only putting out a mono-like sound. Testing reveals the following --

Having drilled down through all the controls, turning down all the sliders in the equalizer still results in some low level of sound, say 2, still bleeding through.

Configuration screen always shows that clicking on one speaker is significantly louder than the other. And left and right sliders control all sound, not only left or right.

Appears not to be a hardware issue, given that all the above work fine when using headphones, and that both speakers, and the subwoofer, are putting out sound, just not at the right levels. The two speakers are not putting out a truly mono signal; that is the effect because only one signal is predominant. In fact, I listened to an old Hendrix song, and it was obvious that only one channel was present. But the software is only controlling the one signal, with the other channel present but significantly lower.

You may need a new sound card. Also, I'd suggest a mixer and a headphone amplifier. The mixer will give you sonic control while the amp will pump some power to the shotty speaker. Usually mixers have preamps built right in. I suggest a cheap Behringer; great mixers (and speakers, amps) that are inexpensive and are very solid quality. CPU's don't have the best sound output control, especially the sound card and input in general. Thats why I rely on a nice tube preamp, Marshall 59' reissue tube stack, an active DI box for balanced signals to a xenyx mixer w/ brit EQ's, and control for sonic mastering. Also if you are using the built-in speakers, just don't... useless.. lol. Even a pair of CPU speakers doesn't do good records any justice. Studio pro quality monitors is the only thing for me. You'll hear things in songs youve never heard. Highly, highly recommend it. Class A/B amplified monitor w a nice ~5" speaker and a 1" tweeter perfecto. Preferably kevlar for the larger speaker, silk for the tweeter. Got way off track but you'd love the sound, I'm a very seasoned musician with a rather good ear. JBL, Bose, ProSonus are among my personal favorites. Good luck!