I have a very old Sound Blaster Audigy that has always worked for me despite its age, I recall being able to select quadraphonic sound back in my old 32-bit Win 7 just fine. Now I am trying to use 4 speakers again, but when I select "quadraphonic" using the windows playback properties dialog, and then test the rear speakers, the demo audio chime switches back and forth between the front and rear speakers, like it can't decide where to output it to (the speakers are connected to the audigy using two 3.5mm stereo jacks; one for the front in the green plug and one for the rear in the black plug). I also tried switching to "4/4.1 Speakers" using the Creative Audio Console, and about 3 seconds after selecting it, it quickly switches my selection back to "2/2.1 Speakers". What the hell?
So I decide to try my motherboard's onboard sound card.
Any ideas why I can't seem to use 4 speakers any more? I have tried rebooting with the speakers plugged in, I'm not running any background programs that could affect the audio.