In this configuration your system should match the configuration of all other users running the default configuration, all properly encoded files (Left channel source audio input recorded to Stereo Channel 1 and Right channel source audio input recorded to Stereo Channel 2) will play correctly in all media applications, and the System Preferences > Sound > Output Blalance slider will work normally. If it doesn't, then your speakers are reverse wired and you really should change their wiring.

If you are in the default configuration mode (left front = Channel 1 and right front = Channel 2) then pressing the 'left front' button will send sound to your left speaker and pressing the 'right front' button will send sound to your right speker. When the new window opens, press the 'left front' and 'right front' buttons under the 'Stereo' tab to generate white noise audio signals and observe through which speaker the noises are played back. To do this, press the press the 'Configure Speakers.' button under the 'Output' tab. What I recommed is that people check to ensure their speakers are wired correctly. Not really sure what you want people to do here. The first step is to ensure your system hardware is properly configured. Will, therefore, go through your list and, for the benefit of other users not already familiar with this process, make some additional amplifying comments of my own. I honestly don't know how to explain things any more simply.

Test speaker channels with balance slider

Divx player ac3 audio codec