2 speakers to pc

So I've been here a long time and would really like a fix plz. So I have speakers and a headset when i plug either in the front IO they both only play through one speaker but if i plug either in the back IO they work great. I've tried restarting and updating drivers. Not sure what to do please...

Hello. I've been informed that usually a Nvidia GPU fits better with a Intel CPU when it comes to performance...but would it really be bad if i tried a Nvidia GPU combined with a AMD CPU...? Incase you wondering wich GPU i'm talking about it's a GTX560 Ti. Regards, Drake.