Need Help :(, New usb monitors, sound from one speaker

I’m running Windows 8 64 bit on a Gateway DX4780-UR368 desktop, and bought a pair of Samson Studio GT monitors today. I hooked them up, and low and behold, I only get sound out of the active monitor (the one on the right side). I noticed that I plugged my headphones up to them and it’s the same issue.

I can take these back for another pair (which I want to do if I have to, because what I heard even out of the one monitor was great), but I want to see if anyone has any suggestions before I make the somewhat long trip again.

I made sure the speaker cables (the positive and negatives) were hooked up correctly, but that made no difference.

Thanks for any help the can be offered.

EDIT: Interestingly, I plugged my headphones into a second phone output on the monitor (It has two). The first time I plugged up to the right phone and accordingly only got right audio. This time, I hooked it up to the left, and only got left audio. But both output are supposed to output stereo.

There must be something I’m missing here.

EDIT #2: It’s definitely something I’m missing. I plugged my iPod to the extra input located on the back of the right monitor, and VIOLA! Sound from both monitors! I’m perplexed why it only gets one output from the USB.

Well, I have found a temporary solution until I figure out how to get it working via USB. I enabled my regular sound card, and have that outputting to the extra RCA input of the monitors. I would like suggestions, though, as these particular monitors (The Samson Studio GT) have an audio interface built in.

Monitors sound great, though. Better than old Numark NPM5’s, which were also great but lacking the highs.

Does this only happen in Cubase or whatever software you are using, or also in other programs or in Windows?

Happens with every program in Windows.

UPDATE: It WAS the speakers after all. I just exchanged them for another pair, and now they work as expected.