audio problem from mobo epox 9nda3

[bkolk]

The audio from the rear of the motherboard epox 9nda3 has 4 audio outputs, front stereo out, side stereo out, rear stereo out, subwoofer out. Now in the sound manager i choose 2channel sound, and plug my stero speakers into the front stereo out, but the sound comes out of one speaker when i do the audio test to test each speaker, it test right speaker first, and it comes out of the left speaker, then tests left speaker and nothing comes out of either. If i plug the same speakers into the front of my case it comes out correctly from each speaker. What is keeping the back of the motherboard from sending audio correctly.

mobo = http://www.newegg.com/Product/Product.asp?Item=N82E16813123222