Only one internal speaker works?? Any solutions?

I have a Japanese computer, lol feel like I have typed that a lot. I installed an english os, then the computer had issues. Couldn't use the net, no sound, etc.. Thank to majorgeek helpers most the issues were fixed.

I was using headset for a while and missed something, seems that there is only sound coming from one internal speaker.

I tried looking at the settings and changing something and nothing.. (I changed it back once it didn't work)

Can anyone help me solve this new issue...??

Thanks,

John