HELP sound coming only from 1 speaker

[p94-t]

Sound only coming out of 1 speaker. (Left)

Mobo: ASUS P5K SE/EPU

Speaker: Logitech LS21 2.1

The sound driver seems to be up to date. Nothing wrong with the speaker because I tried it on my laptop and its totally fine.
So, i guess its the mobo jack. Although my old speakers worked fine. (I do not have any sound card. Currently using on board card.)

What can you suggest me?

 

[Engima]

Have you check the sound settings in the Control Panel?

 

[p94-t]

Yes, I have done possibly everything related to software. Nothing works. Expect something new suggested.